Members of the commission shall receive per diem according to law and are to be granted administrative leave with full pay by their employer for time spent in the performance of official duties under AS 14.20.370 - 14.20.510. If a member is required to spend more than 15 days in a fiscal year in the performance of official duties under AS 14.20.370 - 14.20.510, the state shall reimburse the employer for costs incurred after the 15th day.