Renewable Fuel Standard Flexibility Act - Amends the Clean Air Act to require the Administrator of the Environmental Protection Agency (EPA): (1) by August 1 and by the end of November each year, to determine and publish the U.S. corn stocks-to-use ratio for the current crop year; and (2) to waive the renewable fuel program's requirements for the rest of the calendar year following the August determination or for the next calendar year following the November determination by reducing the national quantity of renewable fuel otherwise required by specified amounts based on the ratio determined.
Prohibits: (1) waivers granted under this Act from affecting the volume of advanced biofuel under such program, or (2) the Administrator from allowing any volume of conventional biofuel to be used to satisfy the requirement for advanced biofuel.