An employee shall continue to be a member of the Arkansas Public Employees' Retirement System if the employee:

1. (1) Was employed before July 1, 1989, as a school janitor, bus driver, or cafeteria worker;
2. (2) Was enrolled in the Arkansas Public Employees’ Retirement System under the provision of Acts 1965, No. 63;
3. (3) Was promoted to a position of school maintenance worker or supervisor, bus mechanic or transportation supervisor, or cafeteria manager, respectively; and
4. (4) Remains employed in the position to which he or she was promoted.