The EPA finalized their rules for the HFC phasedown including production and consumption baselines which will be reduced over time. The rule establishes a phasedown schedule, a method for trading allowances, and an enforcement system. The final rule can be found here: Phasedown of Hydrofluorocarbons: Establishing the Allowance Allocation and Trading Program under the American Innovation and Manufacturing Act.
More information about the HFC phasedown can be found in these articles:
U.S. Will Dramatically Cut Climate-Damaging Greenhouse Gases with New Program Aimed at Chemicals Used in Air Conditioning, Refrigeration
HFC Phasedown Frequently Asked Questions
HFC Phasedown Issuing Allowance Allocations.