(1) Except as provided in subsection (2), a member may not purchase more than a combined total of 5 years under 19-3-503, 19-3-511 (3)(b), 19-3-512, 19-3-513, and 19-3-515.
(2) A member who has purchased service credit under 19-3-503 or 19-3-512 on or before January 1, 1990, and who elects to purchase service credit under 19-3-513 must receive credit for the full months of service credit purchased on or before January 1, 1990.