This proceeding requires us, for the first time, to chart the interrelationship between Fed.R.App.P. 4(b) (delimiting the appeal period in criminal cases) and Fed.R.Crim.P. 35(c) (the text of which is set forth in the margin). 1 We conclude that, under certain circumscribed circumstances, post-judgment motions brought under the latter rule can operate to extend the appeal period limned by the former rule, and that the instant case qualifies for this elongating effect. Thus, the appeal prosecuted by defendant-appellant Josh Morillo is properly before us. This initial success heralds a hollow victory, however, for we find Morillo’s substantive arguments unpersuasive and affirm the judgment below.
I.
Background
A thumbnail sketch suffices to put this appeal into workable perspective. 2 In 1992, a federal grand jury indicted appellant on three counts of distributing heroin in violation of 21 U.S.C. § 841(a)(1) (1988). He entered a plea of not guilty. The district court set the case for trial in December. On November 30, appellant moved for the appointment of an independent toxicologist to weigh the drugs that the government planned to offer in evidence against him. He made it clear that he was ready to plead guilty to the charges but for the dispute over drug quantity. On December 10, 1992, without any agreement anent weight, appellant changed his plea and acknowledged his guilt on all counts. Some two months later the district court granted appellant’s longstanding motion and ordered the drugs reweighed at a state-run laboratory. The laboratory reported its findings soon thereafter.
At a sentencing hearing held on March 18, 1993, the district court determined that the heroin involved in the counts of conviction warranted a base offense level (BOL) -of 18. See U.S.S.G. § 2Dl.l(c)(13) (Drug Quantity Table). 3 The judge increased the BOL by two levels because of Morillo’s aggravating role in the offense, see U.S.S.G. § 3Bl.l(e), and decreased the BOL by two levels for acceptance of responsibility, see id. § 3El.l(a). When combined with appellant’s criminal history category (III), the various adjustments produced a guideline sentencing range (GSR) of 33-41 months. The court sentenced appellant at the range’s apex and entered final judgment on March 19, 1993.
On March 23, appellant filed a motion asking the court to correct his sentence because of an alleged miscalculation in figuring drug quantity. On April 1, appellant filed a notice of appeal. On April 19, the district court *867 addressed appellant’s post-judgment motion and denied- it by means of a margin order. Appellant did not file a further notice of appeal.
II.
Appellate Jurisdiction
A.
Suspensory Motions: An Overview
In a criminal case, a defendant must appeal within 10 days after entry of a judgment of conviction.
See
Fed.R.App.P. 4(b). Because the obligation is mandatory and jurisdictional, unexcused failures of compliance inevitably result in the loss of appeal rights.
See United States v. Kress,
Post-judgment motions apart from those expressly enumerated in Fed.R.App.P. 4(b) can have the same suspensory effect. The paradigmatic example is a timely motion for rehearing or reconsideration.
See United States v. Ibarra,
— U.S. —, —,
B.
Framing The Issue.
The pivotal question here is whether appellant’s post-judgment motion is of this sus-pensory genre. 4 If the filing of the motion did not interrupt the progress of the appeal period, then Fed.R.App.P. 4(b) applies without dilution and Morillo’s notice of appeal, filed more than 10 days after entry of judgment, is a nullity. To avoid this result, appellant must convince us that bringing the March 23 motion suspended the running of the appeal period by rendering the original judgment nonfinal for appeal purposes, or, put in its simplest aspect, extended the time within which an appeal from the underlying judgment could be taken.
C.
Analysis
1.
Characterization.
Our first order of business is to determine the character of the March 23 motion. The motion did not invoke, or even refer to, any particular procedural rule. When a motion is silent as to the location of its procedural moorings, an inquiring court must look to the motion’s substance, including the relief requested, in order properly to characterize it.
See, e.g., Dieter,
Here, appellant styled his motion as a motion “to correct sentence.” Elevating substance over form, we conclude that the motion invokes, or is at least the functional equivalent of a motion brought pursuant to, Fed.R.Crim.P. 35(c), quoted
supra
note 1. The motion posits, in fairly blunt terms, that the district court made a numerical mistake in its aggregation of discerned drug quantities. Whether or not one classifies this claimed bevue as “arithmetical,” the motion alleges, at a bare minimum, a strain of “clear error.” This is the very sort of situation that Rule 35(c) was designed to address.
See
Fed.R.Crim.P. 35(c) advisory committee’s note (199.1 amendment) (stating that the rule enables a court to rectify “an obvious error or mistake” affecting the sentence so long as the error or mistake is “discovered shortly after the sentence is imposed”);
see also United States v. Corey,
2. Effect. Having identified the motion as a motion under Fed.R.Crim.P. 35(c), the lens of inquiry narrows. We focus next on whether a motion brought pursuant to Rule 35(c) extends the time for appealing from the underlying judgment. 5 We conclude that it does.
It is settled beyond peradventure that a timely motion for rehearing or reconsideration of a judgment in a criminal case interrupts the original appeal period. See supra p. 867 (listing precedents). This tenet applies in criminal cases notwithstanding that, by and large, there are “no explicit provisions for rehearing proceedings in criminal cases.” 16 Charles A. Wright et al., Federal Practice & Procedure § 3950, at 482 (Supp. 1993). Justice Harlan, writing for a unanimous Court, explained the rationale for giving such motions suspensory effect:
[Depriving parties to a criminal case] of the opportunity to petition a lower court for the correction of errors might, in some circumstances, actually prolong the process of litigation — since plenary consideration of a question of law [on appeal] ordinarily consumes more time than disposition of a petition for rehearing — and could, in some cases, impose an added and unnecessary burden of adjudication upon [the appellate court].
Healy,
It stands to reason that, if a sentence is infected by clear error, a timely motion seeking to correct it — at least a motion which, like this one, seeks to shrink the incarcerative portion of the sentence and, thus, carries the potential to affect substantive rights — fits the
Healy
mold. Forcing a party to press ahead with an appeal while such a motion is pending would countervail the principles of efficacy and judicial economy that undergird
Healy.
Consequently, we hold that when, as now, a party to a criminal case files a timely motion under Fed. R.Crim.P. 35(c), asking the sentencing court to reconsider an issue in the case in a way that will, if successful, bring about an alteration of the defendant’s substantive rights, then the filing of that motion renders the
*869
judgment nonfinal for purposes of appeal.
6
Accord Corey,
3.
Timeliness.
Our speleology into this jurisdictional cave also uncovers a temporal dimension. We have been careful to note, and believe it is prudent to emphasize, that only a
timely
motion for rehearing or reconsideration should be accorded suspenso-ry effect.
See, e.g., Dieter,
In precincts patrolled by Rule 35(c), however, the
Carr
formulation is overgenerous. The drafters of the rule were concerned lest they pave further avenues of delay within the criminal justice system. To assuage this concern, the rule states that a court may act thereunder “within 7 days after the imposition of sentence.” .Fed.R.Crim.P. 35(c). The interval constitutes a limitation,
see
Fed. R.Crim.P. 35(c) advisory committee’s note (1991 amendment) (discussing the new rule’s “stringent time requirement”) — and the limitation is absolute: if no motion is made within the seven-day period, .none can be made thereafter; and, moreover, if a motion is timely made but is not decided within the seven-day period, the judge’s power to act under the rule subsides and the pending motion is deemed to be denied as of that date. Judge Easterbrook neatly captured the essence of the limitation: “The district court’s inaction ha[s] the same effect as denying the motion, making the judgment final on the date the district judge’s power to alter the sentence expired.”
United States v. Turner,
We derive two valuable lessons from the anatomy of the rule: (1) a motion under Rule 35(c) interrupts the appeal period and renders a judgment nonfinal only if it is brought within seven days following the imposition of sentence; and (2) the appeal period is restarted when the district court decides a timeous Rule 35(c) motion or at the expiration of seven days next following imposition of sentence, whichever first occurs.
4. Application. In this case, the district court pronounced sentence on March 18 and entered judgment the next day. 8 Appellant filed his Rule 35(c) motion on March 23, comfortably within the seven-day period. The district court did not act immediately upon the motion and, consequently, the pen-dency of the motion rendered the judgment nonfinal only through the end of the seven-day period, when the appeal period restarted. From that point forward, appellant had 10 days within which to docket his appeal. See Fed.R.App.P. 4(b). By filing a notice of appeal on April 1, 1993, he met the deadline *870 with room to spare. Hence, the appeal is properly before us. 9
III.
The Merits
A.
Drug Quantity
Under the guidelines, drug quantity is “a key datum” in the sentencing of narcotics offenders.
United States v. Bradley,
The facts relating to the dispute over drug quantity can be succinctly summarized. Defendant was charged with distributing heroin on three occasions: February 7, 20, and 21, 1992. Each transaction culminated in the exchange of a substantial number of “browns,” individually packaged for street-level sales. Immediately following each transaction, the federal Drug Enforcement Administration (DEA) estimated the weight of the purveyed drugs by representative sampling, that is, by weighing a few of the “browns” and multiplying the average weight by the total number of packs contained in the consignment. On this basis, the DEA reported that the first transaction involved 6.51 grams of heroin, the second transaction involved 1.24 grams, and the final transaction involved 20.30 grams. Appellant contested only the last of these three assessments. Pursuant to the district court’s order, the state toxicology laboratory studied the heroin involved in the third transaction, using its own formula, and estimated that it weighed between 10.39 and 16.21 grams. Of necessity, however, this estimate did not include the weight of the heroin previously extracted from the third batch by the DEA, used in arriving at the DEA’s drug quantity determination, and never replaced.
Faced with these competing estimates, the judge found it probable that the third batch contained at least 12 grams. This total, when augmented by the weight of the drugs from the first two transactions (6.51 and 1.24 grams, respectively) and the sample amount originally extracted from the third transaction (0.41 grams), brought the drug quantity over 20 grams and the BOL to 18. 11
*871
The government has the burden of proving drug quantity by a fair preponderance of the evidence.
See United States v. Sklar,
We discern no error here. When it is impossible or impractical to obtain an exact drug quantity for sentencing purposes, a reasoned estimate will suffice.
See Sklar,
B.
Acceptance of Responsibility
The district court found that appellant had accepted responsibility for his criminality and trimmed his offense level by two levels on that account, see U.S.S.G. § 3El.l(a), but refused to grant an additional one-level credit under U.S.S.G. § 3El.l(b). 12 Appellant assigns error to this refusal, eyeing a further reduction pursuant to section 3E1.1(b)(2).
A defendant bears the burden of proving entitlement to decreases in the offense level, including downward adjustments for acceptance of responsibility.
See, e.g., United States v. Ocasio-Rivera,
We find no clear error in the district court’s determination that appellant failed to qualify for the added discount under section 3El.l(b)(2). Appellant was arraigned on October 20, 1992. He pleaded not guilty. Several weeks later, in his November 30 motion for the appointment of an independent toxicologist, appellant indicated that he was “prepared to plead guilty to the three
*872
charges ... but for the dispute as to the weight” of the drugs. In our view, notification of an intention to enter a guilty plea, subject to a major condition, is far too problematic to meet the standard of section 3E 1.1 (b)(2). That provision was designed to allow the government and the district court to conserve resources by avoiding unnecessary trial preparation.
See, e.g., United States v. Lombardi,
There is little more that need be said. Appellant did not plead unconditionally until December 10, 1992 — the very date that the court had set for jury selection. A defendant who withholds a guilty plea until he stands poised on the brink of trial has no entitlement to the soothing unguent of section 3El.l(b)(2). Therefore, the court below acted appropriately in awarding appellant a two-level, rather than a three-level, decrease for acceptance of responsibility.
c.
Role in the Offense
Finally, appellant claims that the district court erred in its determination of his role in the criminal activity.
See
U.S.S.G. § 3Bl.l(c) (providing a two-level increase for assuming managerial responsibilities in certain criminal endeavors). Boosting a defendant’s BOL by two levels under this provision is justified if the sentencing court determines that the offense(s) of conviction involved at least two participants,
13
and that the defendant exercised control over one of them.
See United States v. Akitoye,
In this case, it is undisputed that at least three people participated in the felonious enterprise: appellant, his supplier (Faustino Moronta, Jr.), and a courier, Oscar Severino. On at least one occasion, appellant paged Severino via beeper, and Severino responded to appellant’s apartment with the merchandise — heroin apparently originating with Mo-ronta. The presentence investigation report (PSI Report) asserted that Severino worked for and under the direction of Morillo. Appellant filed written objections to several aspects of the PSI Report, but he did not object to this determination. At the sentencing hearing, appellant’s attorney argued briefly that his client was only a middleman in the criminal transaction; while conceding that Severino brought the drugs to the desired locus at appellant’s behest, counsel claimed that Severino did so as Moronta’s agent — and that Morillo exercised no independent control over him. Yet, appellant offered no evidence to contradict the assertion contained in the PSI Report. Not surprisingly, then, the district court accepted the probation officer’s version of the chain of command.
Facts contained in a presentence report ordinarily are considered reliable evidence for sentencing purposes.
See United States v. Zuleta-Alvarez,
We need go no further. Mindful that appellate review of role-in-the-offense determinations is conducted under a deferential “clear error” standard,
see United States v. Savoie,
Affirmed.
Notes
.The rule provides:
The court, acting within 7 days after the imposition of sentence, may correct a sentence that was imposed as a result of arithmetical, technical, or other clear error.
Fed.R.Crim.P. 35(c). This provision has been in effect only since December, 1991.
. The November 1992 edition of the federal sentencing guidelines applies in this case.
See United States v. Harotunian,
. In Part III(A), infra, we discuss the relevant details of the debate over drug weight and, relat-edly, the appropriateness of the BOL.
. We use the term "suspensory” because, although some courts and litigants describe the effect of such motions as "tolling” the time for appeal, that description is inaccurate. Because the appeal period begins to run afresh at the time of disposition of the motion, the motion does not toll the appeal period, but restarts it.
See Ibarra,
-U.S. at-n. 2,
. To be sure, the text of Rule 35(c) does not mention motions and contemplates that the district court, within certain specified constraints, may act
sua sponte
to correct sentencing errors. But we do not read the rule as prohibiting either the government or the defendant from calling the need for corrective action to the sentencing court’s attention by means of a timely filed post-judgment motion. We believe that such motions are permissible and note that other courts have read the rule as authorizing them.
See, e.g., Corey,
. The likelihood that appellant might prevail on his motion is irrelevant for purposes of determining the motion’s suspensory effect.
See Ibarra,
-U.S. at-,
. The events in
Carr
antedated the adoption of Rule 35(c).
See Carr,
. For ease in reference we use March 19 as the dispositive date. Withal, we note that Rule 35(c) purports to measure the seven-day period from "the imposition of sentence.” We think it is likely that when the two dates differ, this phrase signifies the date judgment enters, rather than the date sentence is orally pronounced.
See Zuleta-Molina,
.There are other questions that might affect the jurisdictional calculus in cases of this stripe — but those questions are not presented on this record. For instance, we have no occasion to consider (i) whether a different result might obtain if it could be shown that a movant brought a post-judgment motion in bad faith,
see Ibarra
, — U.S. at-n. 3,
. For example, in Morillo's criminal history category (III), the spread between the high end of a Level 18 GSR (41 months) and the low end of a Level 16 GSR (27 months) is 14 months.
. Appellant’s post-judgment motion claimed clear error on the theory that the judge intended to aggregate only the first three of the quantities mentioned in the text. In rejecting the Rule 35(c) motion, however, Judge Lagueux made it clear that he also intended to include the sample amount from the final transaction.
. The applicable guideline reads:
(а) If the defendant clearly demonstrates acceptance of responsibility for his offense, decrease the offense level by 2 levels.
(б) If the defendant qualifies for a decrease under subsection (a), the offense level determined prior to the operation of subsection (a) is level 16 or greater, and the defendant has assisted authorities in the investigation or prosecution of his own misconduct by taking one or more of the following steps:
(1) timely providing complete information to the government concerning his own involvement in the offense; or
(2) timely notifying authorities of his intention to enter a plea of guilty, thereby permitting the government to avoid preparing for trial and permitting the court to allocate its resources efficiently, decrease the offense level by 1 additional level.
U.S.S.G. § 3E1.1.
. The defendant himself may be counted in determining the overall number of participants.
See United States
v.
Preakos,
