(a) A member who has five or more years of credited service upon termination of employment shall be automatically vested and entitled to a deferred vested benefit to be computed in accordance with the provisions of section 516(b) of the Retirement and Social Security Law. Such deferred vested benefit may be paid in the form of an early service retirement benefit, or may be postponed until after normal retirement age, in which event the benefit will be subject to reduction or escalation as provided in section 504(c) of the Retirement and Social Security Law.

(b) In lieu of the rights set forth in subdivision (a) of this section, such a member may elect to receive the rights set forth in section 5009.4 of this Part. However, in the event of such an election, the member will receive only the benefits provided under article 15 of the Retirement and Social Security Law, and may not mix the provisions of article 14 and article 15 to change the eligibility requirements for a benefit under either article.