A. The time of service herein specified shall be computed from the time of the first or original service to the City and need not be continuous.
B. If, after the expiration of authorized sick leave, an employee although without pay, is absent from work, such employee, upon presentation of satisfactory evidence to the Board that such absence was because of health, will be given credit for pension purposes only for an additional period not exceeding 90 calendar days total during the entire period of service with the City; provided, however, said employee contributed to the pension fund for such period of absence an amount which is equal to the sum he would have contributed had he been working, based on his salary or wages, for a full regular work week at the contributing percentage in force for such employee.