Sec. 5.06. VESTED RIGHTS OF GROUP B MEMBERS. (a) If a Group B member accrues five years of pension service, whether the pension service is accrued while a Group B member or while a member of the old plan, Plan B, Plan A, the combined pension plan, or a combination of the plans, the Group B member has vested rights and is eligible to apply for a retirement pension in accordance with Section 6.02 of this article.

(b) If a Group B member has vested rights as determined under Subsection (a) of this section, and the Group B member either voluntarily or involuntarily leaves active service before becoming eligible to receive any benefits under Section 6.02 of this article, the person shall be provided with a letter approved by the board and signed by the executive director that, barring unrepaid refunds, clerical error, miscalculation, or other error, is incontestable and shall state:

(1) the total amount of pension service the Group B member had accrued until the date the person left active service;

(2) the total amount of contributions the Group B member made under the terms of Plan B and the combined pension plan; and

(3) the monthly retirement pension due the Group B member at age 58.