(a) Within 30 days after the certification of a land use plan, or any portion thereof, the commission shall, after consultation with the appropriate local government, establish a date for that local government to submit the zoning ordinances, zoning district maps, and, where necessary, other implementing actions. In no event shall that date be later than January 1, 1984.
(b) If a local government fails to meet the schedule established pursuant to subdivision (a), the commission may waive the deadlines for commission action on submitted zoning ordinances, zoning district maps, and, where necessary, other implementing actions, as set forth in Sections 30511 and 30513.