Mich. Comp. Laws § 38.1369f

Sec. 69f. (1) Until September 29, 2017 at 5 p.m. Eastern Daylight Saving Time, a member may elect to purchase not more than 5 years of service credit less the number of years of service credit purchased under sections 6(2)(c), (d), (e), and (f), 64(3), (4), and (5), and 69c(2), or former sections 69a, 69b, 69d, 69e, 74a, 74b, 77, and 78, on request and payment to the retirement system of the actuarial cost. (2) Service credit purchased under this section must not be used to satisfy the minimum of 10 years of service credit required to receive a retirement allowance under this act. (3) Service credit purchased under this section must not be used to satisfy the service credit requirement set forth in section 81(1)(a) for a retirement allowance paid before age 46 as provided by section 43b(a). (4) If a member who made payment for service under this section dies and a retirement allowance is not payable, or if the member withdraws from service and a retirement allowance is not payable, the payment made by the member must be refunded to the member or to the member's refund beneficiary upon request. (5) After September 29, 2017 at 5 p.m. Eastern Daylight Saving Time, a member is not eligible to initiate a service credit purchase under this section.