Section 5-8-8 - Time for assessment and collection of feeA. Assessments of an impact fee shall be made at the earliest possible time. Collection of the impact fee shall occur at the latest possible time. B. For land that has been platted in accordance with the subdivision or platting procedures of a municipality or county before the effective date of the Development Fees Act or for land on which new development occurs or is proposed without platting, the municipality or county may assess the impact fees at the time of development approval or issuance of a building permit, whichever date is earlier. The assessment shall be valid for a period of not less than four years from the date of development approval or issuance of a building permit, whichever date is earlier. C. For land that is platted after the effective date of the Development Fees Act, the municipality or county shall assess the fees at the time of recording of the subdivision plat and this assessment shall be valid for a period of not less than four years from the date of recording of the plat. D. Collection of impact fees shall occur no earlier than the date of issuance of a building permit. E. For new development that is platted in accordance with the subdivision or platting procedures of a municipality or county before the adoption of an impact fee, an impact fee shall not be collected on any service unit for which a valid building permit has been issued. F. After the expiration of the four-year period described in Subsections B and C of this section, a municipality or county may adjust the assessed impact fee to the level of current impact fees as provided in the Development Fees Act.