A school administrative unit shall grant a certified teacher, except a substitute teacher as defined by the commissioner, leave of absence without pay and without forfeiture of continuing contract status and other accumulated benefits to fulfill the duties of a Legislator, provided that the teacher provides a written notice of intent to become a candidate for the Legislature at the time teacher contracts are issued.   [PL 1981, c. 693, §§ 5, 8 (NEW).]