(a)
A nonmember entitled to receive a retirement allowance shall receive a retirement allowance based on the service retirement formula applicable to the service credited to the nonmember.
(b)
The retirement allowance shall consist of a pension and an annuity, the latter of which shall be derived from the nonmember’s accumulated contributions. The nonmember’s retirement allowance, based upon the service credited by the employer and the nonmember’s effective date of retirement,
shall be subject to all cost-of-living increases, ad hoc increases, and increases provided by Section 21337 or 21337.1.
(c)
If, prior to the nonmember’s retirement, there is any increase in the service retirement formula that applies to service credited to the nonmember, that increase shall apply to the applicable service credited to the nonmember, provided that the same increase also applies to the applicable service credited to the member from whose account the nonmember’s service was derived.