Notwithstanding the rulemaking provisions of the Administrative Procedure Act (Chapter 3.5 (commencing with Section 11340) of Part 1 of Division 3 of Title 2 of the Government Code), the department may do both of the following:
(a) Implement all waivers approved by the United States Secretary of Agriculture for a period of less than 24 months through all-county letters or similar instructions.
(b) Implement all waivers approved by the United States Secretary of Agriculture for a period of 24 months or longer through all-county letters or similar instructions until regulations are adopted, which shall occur no later than 24 months after implementation occurs.