Notwithstanding the provisions of Kan. Stat. Ann. §§ 74-4902, 74-4911 and 74-4913, to the contrary, an employee who was employed by a participating employer on December 9, 1971, and who was born August 18, 1912, shall be an eligible member of the Kansas public employees retirement system as of January 1, 1972, upon the payment of the appropriate employer and employee contribution and shall be entitled to receive participating service credit for employment with said participating employer from date of membership. Upon the attainment of membership by the provisions of this act, such employee and his or her participating employer shall thereafter be governed by the provisions of the Kansas public employees retirement act.