(a) This section applies only to a former member, member, retiree, or surviving beneficiary of the Employees’ Retirement System or the Teachers’ Retirement System who is subject to the Selection C (Combination Formula) as provided in § 22-221 of this article and to Subtitle 2, Part II of this title.

(b) Except as provided in subsection (c) of this section, a member who is subject to the contributory pension benefit under Subtitle 2, Part II of this title may purchase credit for eligibility service for the period of employment from July 1, 1998 through June 30, 1999, or, if an employee of a participating governmental unit, from July 1, 1998 through the effective date of election of the member’s participating employer, by paying to the Board of Trustees:

(1) on or before June 30, 2000, the amount the member would have been required to contribute for that period of employment; or

(2) on or after July 1, 2000, the amount the member would have been required to contribute for that period of employment plus regular interest compounded annually.

(c) If the member fails to make the payment as provided under subsection (b) of this section, the Board of Trustees shall reduce actuarially the allowance payable to a former member, retiree, or surviving beneficiary of a deceased member, former member, or retiree.