(a)
In addition to the increase of allowance authorized by and granted pursuant to Section 21313 and notwithstanding the limitation in subdivision (b) of Section 21329, any monthly allowance computed under or limited by a retirement formula applicable to local miscellaneous members who retired prior to July 1, 1971, or to local miscellaneous members who so retired and then were reinstated from retirement and retired again after July 1, 1971, and whose allowance is based upon such a formula and paid with respect to a local miscellaneous
member whose retirement or whose initial retirement or death before retirement occurred prior to July 1, 1971, shall be increased by 15 percent. The percentage shall be applied to the allowance payable on the date this section becomes applicable to the contracting agency and the allowance as so increased shall be paid for time on and after that date and until the first day of April immediately following the date of the application. The base allowance shall be increased by the same percentage for annual adjustments beginning with the adjustment effective for time commencing with that annual adjustment.
(b)
This section shall apply only to the portion of the allowance that is based on service in employment with the employer electing to be subject to this section.
(c)
This section shall not apply to any contracting agency nor to the employees of any contracting agency unless that
agency elected to be subject to the provisions of this section in its contract with the board on or before December 31, 2001.