Any member upon his or her retirement for service before attainment of the minimum age of qualification for his or her primary benefit under the Social Security provisions may elect to adjust his or her retirement allowance under the system, effective on the effective date of such allowance, by an increase from time prior to his or her attainment of such age and a decrease from time on and after his or her attainment of such age, provided that: (a) the amount of the increase and decrease shall be actuarially equivalent; (b) the adjustment shall be based on an estimated reduction in his or her retirement allowance pursuant to the provisions of Section 2.124.1810 of this chapter, if determined in accordance with such provisions as in effect on the effective date of his or her retirement under the system, and by taking into account only his or her coverage under such provisions, prior to such effective date; (c) the increase shall not be modified under an option provided by this chapter; (d) such election shall be irrevocable; (e) such election may not be executed earlier than ninety (90) days before the effective date of his or her retirement allowance and shall be effective only if executed on a form provided by the retirement system manager and filed with the manager prior to the date on which the first payment on account of his or her retirement allowance is made. (Ord. 2000-017 § 4(a)(8); prior code § 34.10.1005)