Ill. Admin. Code tit. 80 § 301.20
It is the responsibility of each agency head to report to the Director any significant changes in the duties of every position within the agency. At the request of an agency, or at the discretion of the Director, a survey, audit, or such other investigation as may be deemed necessary by the Director shall be made to determine the proper allocation of any position to a class. Upon written request of an employee, such investigation as may be deemed necessary by the Director shall be made to determine the proper allocation of the employee's position. After making such survey, audit, or other investigation, the Department of Central Management Services shall notify the agency in which such position is located of its decision as to the proper allocation of the position in question. It shall be the responsibility of the head of the agency in which the position is located to notify the incumbent in said position of the decision of the Department of Central Management Services.
Ill. Admin. Code tit. 80, § 301.20