Notwithstanding the provisions of Kan. Stat. Ann. §§ 74-4911 and 74-4913, and amendments to these sections, to the contrary, an employee who became a member of the Kansas public employees retirement system on January 18, 1981, and who was employed by the same participating employer from December 1974 to the present shall have the membership date amended to December 1, 1974, and participating service shall be granted for the period of December 1, 1974, to January 18, 1981, upon receipt of the appropriate employee and employer contributions.