(a) A person who retired and selected an optional cash balance annuity described by Section 840A.054(c)(1), (2), or (5) may change the optional annuity to a standard cash balance annuity only if:
(1) pursuant to a divorce decree, a court orders the change in the annuity to a standard cash balance annuity; or
(2) the retiree files with the retirement system a request to change the annuity and, in connection with a divorce between the retiree and the beneficiary designated by the retiree under Section 840A.054(b), the beneficiary has executed a written, notarized instrument that:
(A) releases the system from any claim to the annuity by the beneficiary; and
(B) transfers all of the beneficiary's interest in the annuity to the retiree.
(b) If a retiree files a request as provided by Subsection (a), the retirement system shall recompute the annuity as a standard cash balance annuity. The increase in the annuity under this section begins with the monthly payment made to the retiree for the month following the month in which a request is filed as provided by Subsection (a).