(a) An annuitant by written request may authorize the retirement system to reduce the annuitant's monthly payment to an amount specified in the request. In writing, the annuitant may subsequently request the retirement system to increase the annuitant's monthly payment to any specified amount that does not exceed the amount payable if a reduction had never been requested.
(b) If the retirement system receives a request under Subsection (a), the director may cause the monthly annuity payment of the requesting annuitant to be reduced or increased as specified in the request.
(c) Any amounts by which an annuity is reduced under this section are forfeited to the retirement system and are not recoverable by any person.