Notwithstanding any of the provisions of

Section to the contrary, each person who, prior to July 1, 1969, was employed in a position, the principal duties of which consist of active law enforcement as defined in

Section 31469.3 or active fire suppression as defined in

Section 31470.4, who has continuously since his or her employment made the salary contributions required of a safety member, and who has continuously since his or her employment been employed in a position which would make such person eligible to become a safety member if he or she had not been over the age of years at the time of his or her employment, shall become a safety member as of the first day of the calendar month following his or her original entrance into the service.

A member who meets the requirements of the preceding paragraph, except that he or she has not made the contributions required of a safety member, may receive credit for such service, as a safety member, when he or she has contributed, with interest to the date paid, the difference between contributions made and those which would have been required if he or she had been a safety member. Such additional contributions are to be made prior to retirement and notice of election to receive credit for service, as a safety member, pursuant to this section, shall be made to the retirement board prior to April 1, 1975. This

section shall not be operative in any county until such time as the board of supervisors shall, by ordinance, make the provisions of the

section applicable in that county.