dissenting:
Regardless of whether it was arbitrary, capricious, or otherwise unlawful for the Commission to provide for the set-off here challenged (a matter on which I express no opinion), that action did not contravene our order in Interstate Natural Gas Ass’n of America v. FERC, 716 F.2d 1 (D.C.Cir.1983), cert. denied, — U.S. -, 104 S.Ct. 1615, 80 L.Ed.2d 144 (1984). That order merely directed the Commission to vacate its rule regarding the manner of computing gas volume, see 18 C.F.R. § 270.204 (1983), which the Commission has done. See Interpretative Rule for Btu Measurement Standard Under the Natural Gas Policy Act, 49 Fed.Reg. 3072 (1984) (codified at 18 C.F.R. § 270.204 (1984)). Even if it be true that a failure to make the prompt refunds that are legally required as a result of vacating the rule would justify mandamus, the Commission retains discretion to determine both the amount and the manner of refund, and appeal rather than mandamus is the only permissible means of asserting that that discretion has been abused. See Quern v. Jordan, 440 U.S. 332, 347 n.18, 99 S.Ct. 1139, 1148 n.18, 59 L.Ed.2d 358 (1979); In re Sanford Fork & Tool Co., 160 U.S. 247, 256, 16 S.Ct. 291, 293, 40 L.Ed. 414 (1895); Gaines v. Rugg, 148 U.S. 228, 239, 13 S.Ct. 611, 615, 37 L.Ed. 432 (1893).
Nor do I believe that the case is properly before us as a petition for review, see 15 U.S.C. § 3416(a)(2) (1982). And even if it were, I would conclude that the only proper forum for review of Order No. 399-A is the Fifth Circuit. Title 28 U.S.C. § 2112(a) (1982) provides:
If proceedings have been instituted in two or more courts of appeals with respect to the same order the agency ... concerned *151shall file the record in that one of such courts in which a proceeding with respect to such order was first instituted. The other courts in which such proceedings are pending shall thereupon transfer them to the court of appeals in which the record has been filed.
Before the present motion was brought before us, a petition for review of Order No. 399 was filed in the Fifth Circuit, see Mobil Oil Exploration & Producing Southeast, Inc. v. FERC, No. 84-4775 (5th Cir. filed Nov. 20, 1984). The petitioners in that case challenged those aspects of Order No. 399 finding that refunds were due and prescribing a formula for their computation — which aspects were affirmed upon reconsideration in Order No. 399-A. The present petitioners challenge those aspects of Order No. 399-A which revised Order No. 399 upon reconsideration so as to require the refunds to be made where possible by offset rather than lump-sum cash payment. While for purposes of determining the necessity of filing a petition for reconsideration before seeking review, see 15 U.S.C. § 3416(a)(2), it may be necessary to consider Order No. 399 (requiring cash refunds) and Order No. 399-A (requiring set-offs instead) to be separate orders, see Public Service Comm’n of New York v. FPC, 543 F.2d 757, 775 n.116 (D.C.Cir.1974); Utah Power & Light Co. v. FPC, 339 F.2d 436, 437-38 (10th Cir.1964), for purposes of effectuating congressional intent in placing review of “the same order” in a single court it seems to me clear that this entire proceeding is one. It makes no sense to review in one court those portions of the proceedings (if indeed it is possible to separate them) determining whether and in what amounts refunds are due, and in another court those portions determining the manner in which the refunds are to be effected. While the agency did not in this instance file the record with the Fifth Circuit, the statutorily prescribed act which has the effect of precluding other courts from entertaining later-filed petitions, see 28 U.S.C. § 2112(a), that court had permitted the omission only because of the representation that a subsequently filed mandamus motion (not a subsequently filed petition for review) was pending before us. See Motion of the Federal Energy Regulatory Commission to Postpone the Filing of the Certificate of Record, Mobil Oil Exploration, supra (Dec. 28, 1984). Once we determine (as we should) that mandamus is unavailable, even if we impermissibly recharacterize the petition for mandamus as an appeal, it is still the second appeal, and precedence must be given to the earlier appeal filed in the Fifth Circuit. The majority’s action frustrates the Congressional policy of preventing piecemeal review and placing review in the court of first filing. If we do not dismiss this case as a meritless petition for mandamus (as we should), we must transfer the so-called appeal to the Fifth Circuit.