Sec. 1C. ALTERNATIVE RETIREMENT PLANS. (a) In this section, "salary-based benefit plan" means a retirement plan provided by the fund under this article that provides member benefits calculated in accordance with a formula that is based on multiple factors, one of which is the member's salary at the time of the member's retirement.

(b) Notwithstanding any other law, including Section 13G of this article, the board and the municipality may enter into a written agreement to offer an alternative retirement plan or plans, including a cash balance retirement plan or plans, if both parties consider it appropriate.

(c) Notwithstanding any other law, including Section 13G of this article, if, beginning with the final risk sharing valuation study prepared under Section 13B of this article on or after July 1, 2021, either the funded ratio of the fund is less than 65 percent as determined in the final risk sharing valuation study without making any adjustments under Section 13E or 13F of this article, or the funded ratio of the fund is less than 65 percent as determined in a revised and restated risk sharing valuation study prepared under Section 13B(a)(7) of this article, the board and the municipality shall, as soon as practicable but not later than the 60th day after the date the determination is made:

(1) enter into a written agreement to establish a cash balance retirement plan that complies with Section 1D of this article; and

(2) require each firefighter first hired by the municipality on or after the 90th day after the date the cash balance retirement plan is established to participate in the cash balance retirement plan established under this subsection instead of participating in the salary-based benefit plan, provided the firefighter would have otherwise been eligible to participate in the salary-based benefit plan.