No member shall be entitled to establish retirement credit for any period during which the member received a retirement allowance; however, should a member return to a position covered by the retirement system, the member shall be able to obtain retirement credit for the month in which the member returns to work even though the member shall keep the member's retirement benefit in the month that the member returns to work as provided in § 8-36-801(a).
T.C.A. § 8-36-804