On September 1, 2023, all powers and duties of the county elections administrator of a county with a population of more than 3.5 million under this subchapter are transferred to the county tax assessor-collector and county clerk. The county tax assessor-collector shall serve as the voter registrar, and the duties and functions of the county clerk that were performed by the administrator revert to the county clerk, unless a transfer of duties and functions occurs under § 12.031 or 31.071.