Upon the issuance of a certificate of appointment by the city council of the city or board of trustees of the village in which the community improvement district is located to a designated community improvement district administrator, the authority of the board of trustees of the community improvement district to exercise the powers of the community improvement district conferred by the Community Improvement District Act shall be suspended. The administrator shall during the period of his or her appointment possess all of the powers of the board of trustees and shall possess exclusive authority to exercise the powers conferred in the Community Improvement District Act.