When no eligibility list exists for a position in the classified service, an employee may receive provisional appointments which may accumulate to a total of 90 working days. A 90-calendar-day interval shall then elapse during which the person will be ineligible to serve in any full-time provisional capacity. No person shall be employed in provisional capacities under a given governing board for a total of more than 126 working days in any one fiscal year, except that when no one is available on an appropriate eligibility list for a part-time position, as defined in Section 88076, successive 90 working days provisional appointments may be made to the part-time position for a total of more than 126 working days in any one fiscal year.