Louisiana Revised Statutes Tit. 48, § 461.5. Removal of nonconforming advertising

Any sign, display or device lawfully in existence along the interstate or primary systems on July 27, 1966 and which is not in conformity with the provisions contained herein shall not be required to be removed until July 1, 1970. Any other sign, display or device lawfully erected which does not conform to the provisions hereof shall not be required to be removed until the end of the fifth year after it becomes nonconforming.