The Federal Trade Commission may, by rule, prescribe and make effective a method of determining the automotive fuel rating of automotive fuel which consists of a blend of two or more quantities of automotive fuel of different automotive fuel ratings if the Federal Trade Commission finds that the method prescribed more accurately reflects the automotive fuel rating of such blend than the weighted-average method set forth in
section 2822(f)(1) of this title. Effective on and after the effective date of such rule, any person shall be considered to satisfy the requirements of
section 2822(f)(1) of this title only if such person utilizes the method prescribed in such rule (in lieu of the method set forth in
section 2822(f)(1) of this title).