Sec. 2B. ALTERNATIVE RETIREMENT PLANS. (a) In this section, "salary-based benefit plan" means a retirement plan provided by the pension system 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 9F of this article, and except as provided by Subsection (c) of this section, the board and the city may enter into a written agreement under Section 27 of this article 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 9F of this article, and except as provided by Subsection (d) of this section, if, beginning with the final risk sharing valuation study prepared under Section 9A of this article on or after July 1, 2021, either the funded ratio of the pension system is less than 65 percent as determined in the final risk sharing valuation study without making any adjustments under Section 9D or 9E of this article, or the funded ratio of the pension system is less than 65 percent as determined in a revised and restated risk sharing valuation study prepared under Section 9A(a)(7) of this article, the board and the city 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 under Section 27 of this article to establish a cash balance retirement plan that complies with Section 2C of this article; and

(2) require each employee first hired by the city 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 employee would have otherwise been eligible to participate in the salary-based benefit plan.

(d) If the city fails to deliver the proceeds of the pension obligation bonds described by Section 9B(j)(1) of this article within the time prescribed by that subdivision, notwithstanding the funded ratio of the pension system, the board and the city may not establish a cash balance retirement plan under Subsection (c) of this section.