Dubuque’s “irrevocable” decision to relocate was not a vote to categorically refuse Dubuque’s overtures, but a vote to insist on financial disclosure as a prelude to bargaining. The Board’s finding that good-faith bargaining between Dubuque and the UFCW might not have been futile was substantially supported by the record. 3. Retroactivity Finally, Dubuque argues that the Board erred by “retroactively” employing its new test in this case. Again, we disagree. Our formulation of the standard for evaluating challenges to the retroactive application of a ruling from an agency adjudication has varied. Compare Retail, Wholesale & Dep’t Store Union v. NLRB, 466 F.2d 380, 390 (D.C.Cir.1972) (applying a five-factor test) with Consolidated Freightways v. NLRB, 892 F.2d 1052, 1058 (D.C.Cir.1989) (<HOLDING>) (internal quotation marks omitted) with
holding no retroactive application recognizing a general principle that retroactive application of rules is permitted absent any manifest injustice holding retroactive application recognizing principle holding that retroactive application of amendments will not result in manifest injustice