Judge KATZMANN concurs in a separate opinion.
JOHN GLEESON, District Judge:
Gilberto Rivera is a crack cocaine offender who was convicted after trial and sentenced in 1996 to a 292-month term of imprisonment. On January 14, 2008, Rivera filed a motion in the United States District Court for the District of Connecticut pursuant to 18 U.S.C. § 3582(c)(2) seeking a reduction of his sentence. Specifically, Rivera sought to benefit from the 2007 decisions by the United States Sentencing Commission (the “Commission”) to (a) reduce the sentences for offenses involving crack and (b) make the reductions retroactive. The district court denied the motion on the ground that Rivera was not eligible for a sentence reduction. Rivera filed this appeal, and we now reverse. Rivera was indeed eligible for a reduction, and we remand the case to the district court for a determination of whether he should receive one.
BACKGROUND
A. Rivera’s Sentence
1. The Calculation of the Guidelines Range
Rivera’s offense involved approximately 3.3 kilograms of crack cocaine. The highest base offense level prescribed by the drug quantity table — Level 38 — applied at the time of his sentencing to all crack offenses involving 1.5 kilograms or more of crack. U.S. Sentencing Guidelines Manual (“U.S.S.G.” or the “Guidelines”) § 2Dl.l(e)(l) (1996). Thus, Rivera’s base offense level was 38, to which there were no adjustments. As for criminal history, Rivera’s prior convictions earned him sufficient points under U.S.S.G. § 4A1.1 to place him in Criminal History Category (“CHC”) IV. The applicable range under the offense guideline was therefore 324-405 months.
However, the nature of Rivera’s convictions subjected him to treatment as a career offender under § 4B1.1.1 Career of[169]*169fender status can affect both the offense level and the CHC. With respect to the former, the career offender guideline provides that the applicable offense level is the higher of the one provided by the offense guideline and the one provided by the chart in § 4Bl.l(b), which sets forth a schedule of offense levels linked to the statutory maximum sentence for the offense of conviction. Since the highest of the levels on that chart is 37, in Rivera’s case the career offender guideline borrowed the offense level of 38 from the offense guideline. As for the CHC, the career offender guideline gives all career offenders a CHC of VI. U.S.S.G. § 4Bl.l(b).
Thus, Rivera’s career offender status affected his Guidelines range by moving him from Level 38, CHC IV, with a corresponding range of 324-405 months, to Level 38, CHC VI, where the range is 360 months to life.
2. The Sentencing Proceeding
At the sentencing on September 10, 1996, the district court (Alan H. Nevas, J.) departed downward from the applicable range of 360 months to life. The basis for the departure was Rivera’s mental health. As the sentencing court noted, the presentence report included a history of head injuries. Rivera had undergone several psychological and neuropsychological assessments to determine his competency in connection with one of his prior prosecutions, and there were strong indications that Rivera suffered from a profound cognitive disability. As a result, the court invoked its power to depart based on Rivera’s mental condition, stating as follows: “[T]he court is going to depart downward three levels pursuant to [U.S.S.G. §§ ] 5H1.3 and 5K2.0.2 The offense level is 35, the criminal history category is six, and the guideline range from the sentencing table is 292 to 365 months.” Having departed downward to that range, the court then imposed a prison sentence equal to its lower end, 292 months.
B. The Motion for a Reduction of Sentence
On January 14, 2008, Rivera filed a motion to reduce his sentence pursuant to the retroactive application of the amended crack guideline. The district court denied the motion and Rivera moved for reconsideration.3 In an unpublished opinion granting the motion for reconsideration but adhering to the initial ruling, the court held that Rivera had failed to satisfy the threshold requirement for a sentence modification, ie., that his applicable guideline range had subsequently been lowered by the Commission. Rivera argued that the applicable range was the post-departure range, that is, the range three offense levels below his career offender range. As discussed further below, the post-departure range had been lowered by the retroactive amendment. The district judge rejected that argument. Relying on, inter alia, United States v. Barton, 595 F.3d 1191 (10th Cir.), cert. denied, — U.S. -, 130 S.Ct. 3444, 177 L.Ed.2d 348 (2010), and United States v. Tolliver, 570 [170]*170F.3d 1062 (8th Cir.2009), the court held that Rivera’s applicable range was the predeparture career offender range, which had not been lowered. United States v. Rivera, No. 94-CR-112 (EBB), 2010 WL 1169767, at *2-3 (D.Conn. Mar. 25, 2010). As a result, the court concluded that Rivera was ineligible for consideration for a sentence modification. See id.
On March 31, 2010, Rivera filed a notice of appeal.
DISCUSSION
A. The Sentencing Commission’s Retroactive Sentence Reductions and the Sentencing Modifications They Authorize '
The Sentencing Reform Act of 1984 (“SRA”), Pub.L. No. 98-473, tit. II, ch. II, 98 Stat.1987, requires the Commission to periodically review the Guidelines and to revise them as appropriate. See 28 U.S.C. § 994(o) (2006). When the Commission amends the Guidelines to lower the sentencing range for a particular offense, it is authorized by the SRA to decide whether and to what extent previously-sentenced offenders may benefit from the change: “If the Commission reduces the term of imprisonment recommended in the guidelines applicable to a particular offense or category of offenses, it shall specify in what circumstances and by what amount the sentences of prisoners serving terms of imprisonment for the offense may be reduced.” § 994(u). As the Supreme Court recently observed, these provisions allow for correction when a particular guideline becomes “a cause of inequality, not a bulwark against it.” Freeman v. United States, — U.S. -, 131 S.Ct. 2685, 2690, 180 L.Ed.2d 519 (2011) (plurality opinion).
The Commission’s exercise of this statutory authority triggers an exception to the general rule that sentencing courts are not authorized to modify sentences after they are imposed. Specifically, 18 U.S.C. § 3582(c)(2) provides that
in the case of a defendant who has been sentenced to a term of imprisonment based on a sentencing range that has subsequently been lowered by the Sentencing Commission pursuant to 28 U.S.C. § 994(o), upon motion of the defendant ... or on its own motion, the court may reduce the term of imprisonment, after considering the factors set forth in section 3553(a) to the extent that they are applicable, if such a reduction is consistent with applicable policy statements issued by the Sentencing Commission.
One of the critical issues in this case is whether Rivera’s sentence was “based on” a subsequently-lowered sentence range within the meaning of § 3582(c)(2).
A retroactive amendment merely authorizes a reduction in sentence; it does not require one. In determining whether to modify a sentence, a judge must consider not only the traditional sentencing factors set forth in 18 U.S.C. § 3553(a), but also the post-sentencing behavior of the defendant and any public safety concerns a reduction in sentence would raise. U.S.S.G. § 1B1.10 cmt. n.l(B). Though a ruling granting or denying an eligible offender’s request for a reduction is reviewed for abuse of discretion, United States v. Borden, 564 F.3d 100, 104 (2d Cir.2009), an order declaring an offender ineligible for one is reviewed de novo, see United States v. McGee, 553 F.3d 225, 226 (2d Cir.2009).
Section 3582(c)(2) grants courts the authority to reduce sentences only if doing so is consistent with the Commission’s applicable policy statements. The relevant policy statement in this regard is U.S.S.G. § 1B1.10, entitled “Reduction in Term of Imprisonment as a Result of Amended [171]*171Guideline Range,” which lists the amendments that the Commission has made retroactive. U.S.S.G. § lB1.10(c). In 2007, at the same time it made the reduced sentences for crack offenses retroactive, the Commission also amended § 1B1.10 to more fully exercise the authority conferred by 28 U.S.C. § 994(u) to dictate when and by what amount an amendment may reduce previously-imposed sentences. Of importance to Rivera’s case are the provisions in § 1B1.10(a) italicized below, which restrict a court’s authority to reduce a sentence to cases in which a retroactive amendment has the effect of lowering the defendant’s “applicable” guideline range:
(1) In General. — In a case in which a defendant is serving a term of imprisonment, and the guideline range applicable to that defendant has subsequently been lowered as a result of an amendment to the Guidelines Manual listed in subsection (c) below, the court may reduce the defendant’s term of imprisonment as provided by 18 U.S.C. § 3582(c)(2). As required by 18 U.S.C. § 3582(c)(2), any such reduction in the defendant’s term of imprisonment shall be consistent with this policy statement.
(2) Exclusions. — A reduction in the defendant’s term of imprisonment is not consistent with this policy statement and therefore is not authorized under 18 U.S.C. § 3582(c)(2) if—
(B) an amendment listed in subsection (c) does not have the effect of lowering the defendant’s applicable guideline range.
U.S.S.G. § lB1.10(a) (emphases added). The Commentary to the section reiterates that eligibility for a sentence reduction “under 18 U.S.C. § 3582(c)(2) is triggered only by an amendment listed in subsection (c) [of § 1B1.10] that lowers the applicable guideline range.” § 1B1.10 cmt. n.l(A).
As for the extent of the permissible reduction in sentence, § 1B1.10(b)(2) provides that “the court shall not reduce the defendant’s term of imprisonment under 18 U.S.C. § 3582(c)(2) and this policy statement to a term that is less than the minimum of the amended guideline range 30....” U.S.S.G. § lB1.10(b)(2)(A). If the original sentence was lower than the applicable range, the policy statement provides for a commensurate reduction in the amended sentence. § lB1.10(b)(2)(B) (“If the original term of imprisonment imposed was less than the term of imprisonment provided by the guideline range applicable to the defendant at the time of sentencing, a reduction comparably less than the amended guideline range ... may be appropriate.”).
Finally, despite United States v. Booker, 543 U.S. 220, 125 S.Ct. 738, 160 L.Ed.2d 621 (2005), which rendered the Guidelines merely advisory, the limitations on the degree of a sentence reduction under § 3582(c)(2) are mandatory: “Section 3582(c)(2)’s text, together with its narrow scope, shows that Congress intended to authorize only a limited adjustment to an otherwise final sentence and not a plenary resentencing proceeding.” Dillon v. United States, — U.S. -, 130 S.Ct. 2683, 2691, 177 L.Ed.2d 271 (2010).
B. Our Precedents
The legal context in which we decide Rivera’s case also includes our own precedents, which establish two important principles. First, if a crack offender who was also a career offender under § 4B1.1 received no downward departure at his initial sentence, he is not eligible for a reduction, at least where “the career offender range ... remains unaltered by the crack cocaine amendments.” United States v. Martinez, 572 F.3d 82, 83 (2d Cir.2009). In those circumstances, the [172]*172sentence was “based on” the career offender range, which has not been lowered by the Commission, rather than the range produced by the amended crack guideline. Id. at 84-85. Martinez is in accord with the holdings of our sister circuits.4
Second, if the sentencing judge in this case had said he was departing from the career offender guideline in order to base the sentence on the range provided by the offense guideline, ie., § 2D1.1, Rivera would be eligible for a sentence reduction. See McGee, 553 F.3d at 228. The defendant in McGee was a career offender, but the sentencing judge determined that the range computed under the career offender guideline overstated the seriousness of McGee’s criminal history. She therefore departed under U.S.S.G. § 4A1.3 to the range produced by the offense guideline (92-115 months), and sentenced McGee to a 115-month term of imprisonment. Id. at 226. Since the actual sentence was explicitly based on the range produced by the offense guideline, and McGee was thus “disadvantaged by the 100-to-l sentencing disparity that the crack amendments sought to correct,” we construed § 3582(c)(2) and § 1B1.10 in a manner that rendered McGee eligible for a reduction. Id. at 230. As discussed further below, unlike Martinez, the precise question we decided in McGee — is a career offender whose sentencing judge departed under § 4A1.3 from the career offender guideline to a sentence based explicitly on the drug offense guideline eligible for a sentence reduction under § 3582(c)(2)?— has sharply divided the circuits.5
C. Analysis
This case is not controlled by Martinez. Though Rivera is a career offender, the sentencing judge departed from the [173]*173range computed under the career offender guideline. Nor is McGee controlling, however, for the sentencing judge did not depart to the range supplied by the offense guideline. Rather, he departed three offense levels from the career offender range based on U.S.S.G. § 5H1.3 because of Rivera’s mental condition. The sentencing judge did not mention the offense guideline or the range it produced in Rivera’s case, and the sentence imposed was below, not within, the offense guideline range. Thus, the argument that was available to the defendant in McGee — that he was sentenced “based on” on a sentencing range calculated pursuant to the since-amended crack guideline — is not available to Rivera.6
The government argues that Rivera is ineligible for relief under § 3582(c)(2) because, notwithstanding the downward departure, he was not sentenced “based on” a range that has subsequently been lowered by the Sentencing Commission, as that statute requires. Rather, it contends, he was sentenced “based on” the career offender guideline, which has not been amended. Relatedly, the government contends that Rivera is ineligible under § 1B1.10 because his “applicable” guideline range, which it asserts is the career offender range, has not been lowered by the retroactive amendment at issue, as that guideline requires.
We hold first that these two issues largely overlap. The Sentencing Commission promulgated § 1B1.10 to implement its statutory authority under § 994(u) to determine when and to what extent sentence reductions are retroactive and, once that authority is exercised, to guide sentencing judges who are considering sentence reductions pursuant to § 3582(c)(2). The statute authorizes a reduction when the original sentence was “based on” a sentencing range that has been lowered; the guideline authorizes one when the range “applicable” at the initial sentence has been lowered. Provisions enacted for the same purpose should be read in pari materia. See, e.g., United States v. Battista, 575 F.3d 226, 234 (2d Cir.2009). We think that the range the initial sentence was “based on” within the meaning of the statute is also generally the range that was “applicable” within the meaning of the guideline. See Darton, 595 F.3d at 1194. Despite the difference in language between the statute and the guideline, we doubt there are many scenarios in which a defendant could qualify for a sentence reduction under one but not the other.
The question before us is this: What range was Rivera’s sentence “based on”— that is, what was his “applicable” sentencing range for purposes of § 3582(c)(2) and § 1B1.10? There are two candidates, as two ranges were implicated at his 1996 sentencing. The first was supplied by the career offender guideline (at least in part), and it was 360 months to life in prison (Offense Level 38/CHC VI). This was the “starting point” of the sentencing proceed[174]*174ing. Freeman, 131 S.Ct. at 2692 (citing Gall v. United States, 552 U.S. 38, 49, 128 S.Ct. 586, 169 L.Ed.2d 445 (2007)). The second range was the one to which the judge departed based on Rivera’s mental condition. It was arrived at by subtracting three offense levels from the career offender computation but remaining in CHC VI. The resulting range was 292-365 months (Offense Level 35/CHC VI), and the sentence imposed was at its low end, 292 months.
The stakes are high for Rivera. If he was sentenced “based on” the career offender range, he is not eligible for a sentence reduction. This is because the retroactive amendment reduces Rivera’s career offender offense level from 38 to 37,7 but that has no effect on the resulting guidelines range; in CHC VI, Offense Levels 37 and 38 both result in ranges of 360 months to life. U.S.S.G. Ch. 5, Pt. A. Thus, Rivera could not satisfy the threshold requirement in both § 3582(c)(2) and § 1B1.10 that a retroactive amendment has lowered the defendant’s applicable range.
On the other hand, if Rivera’s sentence was “based on” the range to which his sentencing judge departed, he is eligible for a sentencing reduction of up to 30 months. The same three-level departure from the revised career offender computation yields an Offense Level of 34 in Criminal History Category VI, with a corresponding range of 262-327 months. As mentioned, a reduction to the bottom of that range would shorten Rivera’s prison term by two and one-half years.
We hold that Rivera’s sentence was “based on” the range produced by subtracting three offense levels from the career offender computation. The resulting range was the one the sentencing judge found to be “applicable” to Rivera, and he chose a sentence at the low end of that range. That range is lowered when the retroactive amendment at issue is plugged into its calculation, even if everything else remains the same. Rivera is therefore eligible for a reduction.
The government contends that the range Rivera’s sentence was based on was the career offender range, but the sentencing judge rejected that range in favor of the one on which he actually based Rivera’s sentence. See United States v. Cardosa, 606 F.3d 16, 20 (1st Cir.2010) (“[T]he government fails to explain why it makes sense to so read ‘based on,’ given that it is a less natural reading and inconsistent with the policy rationale for both the statute and amendments in this case.”). To be sure, the career offender range was the starting point of Rivera’s sentencing proceeding, but then the judging began, and because of Rivera’s mental condition that range was deemed inapplicable. The sentence imposed was based explicitly on the post-departure range, which has since been lowered. See Freeman, 131 S.Ct. at 2695 (Sotomayor, J., concurring in the judgment) (“To ask whether a particular term of imprisonment is ‘based on’ a Guidelines sentencing range is to ask whether that range serves as the basis or foundation for the term of imprisonment. ... As a result, in applying § 3582(c)(2) a court must discern the foun[175]*175dation for the term of imprisonment imposed by the sentencing judge.”).
Our reading of the plain wording of § 3582(c)(2) is further supported by McGee. In rejecting the government’s argument that McGee’s sentence was “based on” the pre-departure, career offender range, as we do again here, we observed that the meaning of the language in § 3582(c)(2) and § 1B1.10 is “inherently contextual.” McGee, 553 F.3d at 229 (quoting United States v. Dauray, 215 F.3d 257, 264 (2d Cir.2000)) (internal quotation marks omitted). It was clear from the sentencing transcript in McGee that the judge had not relied on the career offender range, and indeed “would likely have considered a different sentence from the one imposed” had the retroactive amendment been in effect at the time. Id. at 228. In those circumstances, we concluded that a holding that the (rejected) career offender range was the “applicable” range for the purposes of § 3582(c)(2) and § 1B1.10 would amount to “excessive formalism,” and that therefore McGee was sentenced “based on” the post-departure range. Id. at 227-29.
The same is true with Rivera. As described above, the starting point for his sentence was a range of 360 months to life (Offense Level 38/CHC VI), but the judge determined that Rivera’s mental condition warranted a three-level departure to Level 35. The judge then imposed a sentence at the bottom of the resulting 292-365 month range. If Rivera’s sentencing range is computed in light of the retroactive amendment, the resulting offense level is 37, not 38. The same three-level departure from that level (again in CHC VI) produces a sentencing range of 262-327 months. Thus, there is ample reason to believe that Rivera would have received a sentence as low as 262 months — 30 months lower than the sentence imposed — had the offense guideline been amended before he was sentenced. In short, Rivera appears to have been “disadvantaged by the 100-to — 1 sentencing disparity that the crack amendments sought to correct,” McGee, 553 F.3d at 230, in precisely the same way as McGee.
Our approach in McGee and in this case accords precisely with our obligation under § 3582(c)(2) and § 1B1.10 to
isolate whatever marginal effect the since-rejected Guideline had on the defendant’s sentence. Working backwards from this purpose, § 3582(c)(2) modification proceedings should be available to permit the district court to revisit a prior sentence to whatever extent the sentencing range in question was a relevant part of the analytic framework the judge used to determine the sentence.
Freeman, 131 S.Ct. at 2692-93 (plurality opinion). The marginal effect of the rejected 100-to-l ratio on Rivera’s sentence is easily isolated. It produced a sentencing range with a low end that is 30 months higher than the exact same methodology would produce today. Accordingly, the district court should be permitted to revisit Rivera’s sentence to the extent allowable under § 3582(c)(2) and § 1B1.10.8
[176]*176Other factors influence our decision as well. One is the context in which we decide this case. Though our task is limited to construing the relevant statutory and Guidelines provisions, we are not required to perform it wearing blinders. Retroactive amendments exist to allow inequalities to be fixed, and the now-infamous 100-to-l ratio was the source of shameful inequalities. The Department of Justice itself characterized that ratio as unjustified, fundamentally unfair and racially discriminatory.9 And it bears emphasis that the 2007 adjustment to the offense guideline for crack offenders at issue in this case was billed by the Commission itself as but “a very small step” toward rectifying that very large injustice. Hon. Ricardo H. Hinojosa, Chair, U.S. Sent’g Comm’n, Opening Remarks at the United States Sentencing Commission Public Hearing on Retroactivity (Nov. 13, 2007), available at http://or.fd.org/CrackRetroactivity% 5CTranscriptlll307.pdf, at 9.10
We recognized in McGee our obligation, both generally and in this specific setting, to let lenity play a role in the construction of the Guidelines where there is doubt about their scope. McGee, 553 F.3d at 228-29. The same holds true when we construe statutes. See, e.g., United States v. Kerley, 544 F.3d 172, 178 (2d Cir.2008) (“If Congress leaves a statute ambiguous ..., ‘the ambiguity should be resolved in favor of lenity.’” (citation omitted)). As discussed above, we believe the plain language of § 3582(c)(2) and § 1B1.10 compel the conclusion that Rivera’s sentence was based on the post-departure range his sentencing judge found applicable to his case — a range that has subsequently been lowered as a result of the Commission’s 2007 amendment. But even if those provisions were ambiguous, the rule of lenity [177]*177would prohibit the narrow construction the government urges upon us here.
In addition, as discussed above, all we decide here is the eligibility of Rivera for a sentence reduction under § 3582(c)(2), not his entitlement to one. See Freeman, 131 S.Ct. at 2694. The latter question is left to the sound discretion of the district court. If there are good reasons why Rivera’s sentence should not be reduced notwithstanding the influence the now-discredited 100-to-l ratio had on it, the district court is free to consider those reasons in determining whether to reduce the sentence.
A contrary holding could produce anomalous and unfair results. The government concedes, as it must in light of McGee, that a career offender convicted of a crack offense is sometimes eligible under § 3582(c)(2) for a reduction if the sentencing judge departed from the otherwise-applicable range. Yet it seeks a rule limiting that eligibility to cases in which the sentencing judge explicitly stated that he or she was departing to the range established by the offense guideline. This case highlights the potential unfairness of such a limitation. Rivera’s career offender range was 360 months to life (Level 38/ CHC VI). His range under the offense guideline was 324-405 months (Level 38/ CHC IV). His range after the district court’s departure was 292-365 months (Level 35/CHC VI). Thus, the sentencing judge in this case departed to a sentence below the range computed under the offense guideline. He might indeed have believed, as did the sentencing judge in McGee, that the range produced by the career offender guideline overrepresented the seriousness of Rivera’s criminal history, see U.S.S.G. § 4A1.3, and that therefore a sentence within the range produced by the offense guideline (324-405 months) was fairer. Had the judge imposed such a sentence and used that reasoning, the government agrees Rivera would be eligible for a sentence reduction. But if Rivera’s sentencing judge harbored that belief, he had no reason to express it, as Rivera’s mental condition warranted an even greater departure under § 5H1.3. Put another way, if the judge had had the foresight to depart in stages — first under § 4A1.3 to the range provided by the offense guideline and then a second departure under § 5H1.3 to 292 months based on Rivera’s mental condition — the government would agree that Rivera is eligible for a sentence reduction under McGee. But the judge’s failure to anticipate that fifteen years later we would be parsing his sentencing methodology in this manner, in the government’s view, should categorically deprive Rivera of the minor and long-overdue relief the 2007 amendment was intended to provide. We decline to adopt this crabbed approach. “There is no reason to deny § 3582(c)(2) relief to defendants who linger in prison pursuant to sentences that would not have been imposed but for a since-rejected, excessive range.” Freeman, 131 S.Ct. at 2690.
Instead, we hold as follows: Where the sentencing judge departs from a range computed under the career offender guideline to a lower range, the sentence imposed was “based on” the latter range for purposes of § 3582(c)(2), and for the purposes of § 1B1.10 that range is the “guideline range applicable” to the defendant. If a subsequently-lowered guideline “was a relevant part of the analytic framework the judge used to determine the sentence,” Freeman, 131 S.Ct. at 2693, the relevant statutory and Guidelines provision require that a § 3582(c)(2) proceeding be available to allow the sentencing court the opportunity to remedy an injustice.
[178]*178D. The Approach of Our Sister Circuits
McGee (and by extension our decision here) is in conflict with the decisions of several other circuits. For example, in Darton, the Tenth Circuit faced the same situation we faced in McGee — a request for a sentence reduction by a career offender who had received a criminal history departure under § 4A1.3 to a sentence within the range produced by the offense guideline. Darton, 595 F.3d at 1193. The defendant argued that the initial sentence was “based on” the post-departure range, which was the “applicable” range under § 1B1.10, but his argument was rejected by the Tenth Circuit. The court’s reasoning was driven by the Guidelines Manual’s definition of the term “departure.” By specifically defining a departure as “a sentence outside the applicable guideline range,” the court reasoned, the Guidelines make clear that “a departure only exists apart from the applicable guideline range; there is no such thing as a departure to the applicable range.” Id. at 1194 (citing definitions of “departure” in the commentary to §§ 1B1.1, 4A1.3 and 5K2.0). Thus, it concluded that “the guideline range to which a court departs cannot constitute the ‘applicable guideline range’ or, in other words, the range upon which the sentence is ‘based’ for purposes of a sentence reduction under § 3582(c).” Id.
Darton relied in part on the Eighth Circuit’s decision in Tolliver, which reached a similar result in a different (and unusual) setting. In Tolliver, the parties engaged in plea bargaining based on the assumption that the crack guideline would yield a range of 188-235 months. Tolliver, 570 F.3d at 1064. However, the probation officer determined that the career offender guideline applied, the court agreed, and Tolliver was sentenced to a 262-month term. Id. Later, Tolliver and the government stipulated to a grant of § 2255 relief on the condition that Tolliver would then be sentenced to a 188-month term. Id. That sentence was imposed, and after the 2007 amendment to the crack sentences, Tolliver sought a reduction under § 3582(c)(2) and § 1B1.10. Id. In finding him ineligible, the Eighth Circuit relied not only on the Guidelines’ definition of the term “departure,” but also on the application instructions for the Guidelines set forth in § 1B1.1. Id. at 1065-66. Those instructions require a sentencing judge to take all the steps necessary to compute the guidelines range before deciding whether any departures are warranted. “It follows,” the court observed, “that ... the application instructions will only permit a departure from the ‘applicable guideline range,’ and thus preclude a departure to the ‘applicable guideline range.’ ” Id. at 1066 (emphases added). Therefore, it held, the career offender range was the defendant’s “applicable” range, and since it had not been lowered by the 2007 amendment, Tolliver was ineligible for a sentence reduction. Id. at 1066-67.11
The Sixth Circuit reached the same result in United States v. Pembrook, 609 F.3d 381 (6th Cir.2010), cert. denied, — U.S. -, 131 S.Ct. 1599, 179 L.Ed.2d 503 (2011). In holding that a sentenced defendant who was indistinguishable from the defendant in McGee was not eligible for a sentence reduction, the court found its “most persuasive support” in the Guidelines’ application instructions relied upon by the court in Tolliver. Id. at 385. Since the order of operations established by [179]*179those instructions makes it clear that departures occur only after the applicable guidelines range has been computed, the court reasoned that “applicable” range for purposes of § 1B1.10 must be the predeparture range. Id. Like the Eighth and Tenth Circuits in Tolliver and Darton, respectively, the Sixth Circuit also found support for its holding in the Guidelines’ definition of the term “departure.” Id.12
Pembrook, Tolliver and Darton are all based on the same flawed premise — that the applicable range for the purpose of a sentencing proceeding must necessarily be the same as the applicable range for the purpose of a subsequent sentence modification. We see no reason why that must be the case. We acknowledge a “natural presumption that identical words used in different parts of the same act are intended to have the same meaning,” Atlantic Cleaners & Dyers, Inc. v. United States, 286 U.S. 427, 433, 52 S.Ct. 607, 76 L.Ed. 1204 (1932), and we agree that the same presumption would generally apply to identical phrases used in different parts of the Guidelines Manual. “But the presumption is not rigid and readily yields whenever there is such variation in the connection in which the words are used as reasonably to warrant the conclusion that they were employed in different parts of the act with different intent.” Id.; see also Helvering v. Stockholms Enskilda Bank, 293 U.S. 84, 87, 55 S.Ct. 50, 79 L.Ed. 211 (1934) (“[S]ince most words admit of different shades of meaning, susceptible of being expanded or abridged to conform to the sense in which they are used, the presumption readily yields to the controlling force of the circumstance that the words, though in the same act, are found in such dissimilar connections as to warrant the conclusion that they were employed in the different parts of the act with different intent.”).
One circumstance in which the presumption is readily rebutted is “[w]here the subject matter to which the words refer is not the same in the several places where they are used,” Atlantic Cleaners & Dyers, 286 U.S. at 433, 52 S.Ct. 607, and that is precisely the situation here. The subject matter of the phrase “applicable guideline range” in the definition of “departure” in the commentary to § 1B1.1 is the defendant’s sentencing, at which time the applicable range is “the starting point and the initial benchmark” of the proceeding. Gall, 552 U.S. at 49, 128 S.Ct. 586. Because the Guidelines themselves contemplate departures from the applicable range (and Booker contemplates variances from it even where departures are unavailable), the starting point is not always the finishing point. Thus, it is true that when Rivera was sentenced, his applicable range was the career offender range of 360 months to life. From there, the sentencing judge departed based on his mental condition to a different range, 292-365 months.
The subject matter of the phrase “guideline range applicable to the defendant” in § 1B1.10 is not a sentencing proceeding but a modification proceeding that occurs after (in this case, more than 10 years after) sentence has been imposed. The question in that context is not what sentence is appropriate, but rather whether the sentence actually imposed should be reduced in light of an intervening retroactive amendment. In that setting, common sense suggests that in deciding whether [180]*180“the guideline range applicable to the defendant has subsequently lowered,” a court should focus on the range that was actually applied by the sentencing judge to the defendant, even if, as in this case, that range differs from the one that was the starting point of initial sentencing proceeding. Now that Rivera seeks a modification of his sentence, the 292-365 month range to which his sentencing judge departed is his applicable range. In concluding otherwise, we respectfully suggest that our sister circuits have “simply misemploy[ed] the ‘presumption that identical words used in different parts of the same act are intended to have the same meaning.’ ” Gen. Dynamics Land Sys., Inc. v. Cline, 540 U.S. 581, 595, 124 S.Ct. 1236, 157 L.Ed.2d 1094 (2004) (quoting Atlantic Cleaners & Dyers, 286 U.S. at 433, 52 S.Ct. 607).
Our conclusion that the “applicable range” may have one meaning for sentencing purposes and another for purposes of a § 3582(c)(2) proceeding finds support in our rationale in Martinez. The defendant there sought a modification under § 3582(c)(2) and contended that his initial sentence was “based on” the offense guideline because the sentencing judge consulted that guideline in calculating his range as a career offender. We disagreed, holding that his applicable range for purposes of § 3582(c) was the end result of the overall guideline range calculus — ie., the career offender range, not the interim steps along the way. Martinez, 572 F.3d at 85. We explained that
“the term ‘sentencing range’ clearly contemplates the end result of the overall guideline calculus, not the series of tentative results reached at various interim steps in the performance of that calculus.” ... Therefore to determine which Guideline a defendant’s sentence is “based on” we look only to the end result of the overall calculus ... and not to the “interim” steps taken by the District Court.
Id. at 84 n. 3 (quoting United States v. Mateo, 560 F.3d 152, 155 (3d Cir.2009)) (emphasis added); see also United States v. Caraballo, 552 F.3d 6, 10 (1st Cir.2008).
When Rivera was sentenced, the offense guideline and the career offender guideline were both interim steps in the sentencing calculus, the end result of which was the lower range to which the sentencing judge departed. Thus, the applicable range at Rivera’s sentencing was the career offender range, but the applicable range for his 3582(c)(2) proceeding is the range on which the sentencing judge actually based his sentence.
Our approach is also consistent with the Supreme Court’s emphasis in Dillon on the fact that a § 3582(c)(2) proceeding is not a resentencing. It is, rather, a limited revisiting of a previously-imposed sentence, during which the analytic framework of the sentence is replicated with one exception — the provision that has been retroactively amended is substituted for the corresponding provision applied at the time of sentencing. See Dillon, 130 S.Ct. at 2691 (citing § lB1.10(b)(l)). By its very nature, then, the focus of the modification proceeding is on the final result of the sentencing proceeding, and the analysis that led to that result. Where the final result is the same as the initial applicable range, as in Martinez, the “applicable guideline” at both the sentencing and the subsequent modification proceeding are the same. But where, as here, the analytic framework of the sentence includes a determination that the defendant falls outside the heartland of the applicable range that was the starting point of the sentencing proceeding, the applicable range at the modification stage will be different.
[181]*181We think Pembrook, Tolliver and Barton strain to avoid the commonsense conclusion that the “guideline range applicable to the defendant” within the meaning of § 1B1.10 is the range that was actually used in sentencing the defendant. In Pembrook, for example, the defendant was actually sentenced within the range produced by the drug offense guideline, which the district court used after departing under § 4A1.3 from the range prescribed by the career offender guideline. Pembrook, 609 F.3d at 383-84. But the Sixth Circuit nonetheless held that the “applicable” range was the career offender range the sentencing court had found inapplicable because it overrepresented the seriousness of the defendant’s criminal past. Id. Though we disagree with the details of the court’s analysis,13 the more important point is the one we made in McGee and reiterate here: the combination of the rule of lenity and the fact that the crack amendments were adopted and made retroactive to ameliorate past sentences that were both fundamentally unfair and racially discriminatory counsels against the government’s crabbed construction of § 3582(c)(2) and § 1B1.10.14
[182]*182We are aware that other courts have found crack offenders ineligible for § 3582(c)(2) reductions in sentence despite the fact that they received Chapter Five-based departures from their career offender ranges, as Rivera did in this case. See United States v. Wesson, 583 F.3d 728, 730-32 (9th Cir.2009) (despite departure grounded on diminished capacity, initial sentence “based on” career offender guideline), cert. denied, — U.S. -, 130 S.Ct. 2071, 176 L.Ed.2d 421 (2010); Caraballo, 552 F.3d at 8, 11-12 (same; departure grounded on medical condition). While there are elements of those courts’ analyses that conflict with our analysis here, a critical distinction eliminates the need for extended discussion of them. Specifically, there was no indication in either case that the retroactive amendment would alter the outcome of the career offender guideline computation, as it does for Rivera (by lowering his offense level from 38 to 37). Thus, even if those defendants’ sentences were found to be “based on” the post-departure range in their cases, it could not be said that that range was lowered by the 2007 amendment. The case before us involves a defendant whose career offender [183]*183computation is indeed altered by the amendment in question, as well as a sentencing methodology that strongly suggests the alteration would have made a difference to the sentencing judge. We need not address here situations in which one of those factors is missing.
Finally, we acknowledge the Sentencing Commission’s proposed amendment to § 1B1.10, see U.S. Sentencing Comm’n, 76 Fed.Reg. 41332 (proposed July 13, 2011). Absent congressional disapproval, that amendment will become effective on November 1, 2011, and it will dramatically alter the landscape for sentenced prisoners who seek to benefit from this year’s retroactive reduction of crack sentences. Among other effects, the proposed amendment will preclude sentence modifications in situations like the one in McGee,15 where we found them permissible, and at least arguably permit them in situations like the one in Williams, see supra n. 8,16 where we found them to be precluded. Indeed, because the amendment will prescribe the precise construction of “applicable guideline range” that we refuse to give the existing guideline, i.e., it is the predeparture range from the initial sentencing, the proposed amendment would render Rivera himself ineligible for a sentence reduction if it were applied to his case. However, because the amendments to § 1B1.10, which abrogate the law of this [184]*184and certain other circuits, are substantive, rather than merely clarifying, see United States v. Sabbeth, 277 F.3d 94, 99 (2d Cir.2002), they cannot fairly be applied retroactively to Rivera’s § 3582(c)(2) proceeding on remand.
CONCLUSION
A remand for the purpose of allowing the district court to exercise the broad discretion afforded by § 3582(c)(2) is consistent with our approach to related sentencing situations. After Booker, we faced the question of how to deal on direct review with sentences imposed before that decision by judges who were under the erroneous impression that the Guidelines were mandatory. Our resolution of the plain error and harmless error issues in such cases was to remand them to the district courts “for determination of whether to resentence,” firm in the belief that “an appellate court will normally be unable to assess the significance of any error that might have been made.” United States v. Crosby, 397 F.3d 103, 117 (2d Cir.2005). When the Supreme Court in Kimbrough v. United States, 552 U.S. 85, 128 S.Ct. 558, 169 L.Ed.2d 481 (2007), made it clear that we had been erroneously inhibiting sentencing judges from deviating from the 100-to-l ratio, we faced a similar plain error issue. Once again, acknowledging “the broad deference that this Circuit has afforded the sentencing discretion of the district courts,” we elected to remand all such cases to give the district courts an opportunity to determine whether, in light of subsequent changes in the law, they would have imposed different sentences. United States v. Regalado, 518 F.3d 143, 147, 149 (2d Cir.2008). Our holding today brings that same approach to an analogous setting. The Commission determined that sentences imposed under the onerous crack guideline should be reexamined. The benefit of that long-overdue measure must not be limited to “arbitrary subset^]” of defendants whose sentences appear to have been influenced by the preamendment guideline. Freeman, 131 S.Ct. at 2695. The best way to remedy the “systematic injustice” produced by the old guideline, id., is to err on the side of empowering the district courts to revisit crack sentences, especially since (a) any actual sentence reduction is committed to the sound discretion of the district courts and (b) the extent of any such reduction has been carefully circumscribed by the Commission. These circumstances counsel in favor of a generous construction of § 3582(c)(2) and § 1B1.10, not the narrow ones adopted by some of our sister circuits.
The order denying Rivera’s motion for a sentence reduction is reversed and the case is remanded for a determination of whether such a reduction is appropriate in his case.