"Academic year": The 12-month period beginning on the first day of the fall term as determined by each employer, or if the employer does not have an academic program divided into terms, then beginning September 1. For the purposes of Section 15-139.5 and subsection (b) of Section 15-139, however, "academic year" means the 12-month period beginning September 1.
40 ILCS 5/15-126.1