Notwithstanding any other provision of law, and with respect only to an election by a contracting agency to amend its contract to become subject to

Section 21369, 21370, or 21363, instead of

Section 21366, the following shall apply: (

a) Members who are on the amending agency’s active payroll on the effective date of the contract amendment shall elect in writing, within days after the notification by the board of the amendment, to be subject to

Section 21363, 21366, or 21370, as applicable, or

Section with respect to all safety service performed for the contracting agency. (

b) Members on the effective date who are former employees of the amending agency and whose service for the amending agency was subject to

Section or

Section 21369, shall retain their rights under the formula in effect at the time their service was credited. (

c) Former members who upon reentry into state service elect to redeposit contributions, shall be subject to

Section 21363, 21369, or 21370, as applicable, with respect to all safety service performed for the amending agency prior to the effective date of the contract amendment. (

d) Notwithstanding

Section 21357, a former member who reinstates to the amending agency as a local safety member shall elect within days of the reinstatement whether to be subject to

Section 21363, 21369, or 21370, as applicable, or

Section with respect to all service with that contracting agency prior to the effective date of the contract amendment. The election shall be effective only if the reinstated member remains in the employment for at least one year subsequent to reinstatement.