(a) Any member who retired prior to October 1, 1975 and who has served in the armed services, as described in Section 16-25-3, shall be entitled to claim such full-time military service and to have all retirement allowances due on or after October 1, 1975 redetermined as if the provisions of said section, as amended, were in effect at the time such member retired; provided, that such retired member pays into the Teachers' Retirement System, in a lump sum prior to October 1, 1976, an amount equal to four percent of the average compensation which was paid to a teacher during each claimed year of full-time military service, plus and together therewith, eight percent interest compounded from the last date of such claimed military service; provided further, that such retired member shall not receive membership service credit for more than four years of military service and shall receive no credit for military service if such member is receiving military service retirement benefits, other than disability allowances or benefits, from any branch of the armed forces or by reason of any such service in any branch of the armed forces or if such member received anything other than an honorable discharge for and including the claimed military service.

(b) Anything in this chapter to the contrary notwithstanding, no retirement allowance payment shall be redetermined for any pay period prior to such retired member's full and complete compliance with the provisions of subsection (a) of this section. Any increase provided in the retirement allowance payment under this section for a member who retired under the provisions of any optional benefit elected pursuant to subsection (g) of Section 16-25-14, as amended, or under any other law or part of law pertaining to the Teachers' Retirement System of Alabama shall accrue only to the retired member, and no person designated to receive any payments after the death of such retired member under the provisions of any such optional benefit shall receive any increase in such payments under this section.