If biweekly payroll periods are established under Kan. Stat. Ann. § 75-5501a, which apply to nine-month employees of the state who are employed and engaged in school employment as teachers, or higher education faculty, or who have as their principal duty academic supervision over such teachers or faculty, the monthly pay of such employees shall be calculated for payment on the prescribed biweekly payment system under all contracts entered into for the school year commencing in the year in which the implementation date occurs.