(a) Except in the case of a participant, who, upon application to the administrator is determined by the administrator to be totally and permanently disabled, a participant, who before he or she earned five years of service credit, ceases to be a volunteer ambulance worker of an ambulance company whose volunteer ambulance workers are eligible to participate in the service award program in which such person participates, shall forfeit his or her service credit upon receipt by the administrator of the list described in section 152.7 of this Part on which he or she is first indicated as having ceased to be a volunteer ambulance worker during the calendar year for which the list is prepared.

(b) If a person whose service credit was forfeited in accordance with subdivision (a) of this section, within the five calendar year period beginning immediately after the calendar year in which he or she ceased to be a volunteer ambulance worker, again becomes a volunteer ambulance worker of an ambulance company whose volunteer ambulance workers are eligible to participate in the program in which such person previously participated, such person's forfeited service credit shall be restored as of December 31st of the first calendar year in which he or she again earns a year of ambulance service credit and again becomes a participant in the program in which he or she formerly was a participant.