An employee of a state agency transferring to a school district of this State or a school district employee transferring to a state agency is permitted to transfer to and retain at his new employer all sick leave he accumulated at his former employer regardless of his employment status at the new employer. Sick leave not to exceed sixty days lost by a school district employee as a result of changing employment from the school district to a state agency or by a state employee as a result of changing employment from a state agency to a school district is restored if the employee was employed by the school district or the state agency after June 28, 1984, and is employed on June 30, 1991.