A nonconforming lot or use, noncomplying structure, or other nonconformity may not be changed except in conformance with the provisions of this Title. Whenever any nonconforming use is changed to a less intensive nonconforming use, such use shall not be changed back to a more intensive nonconforming use. Whenever any nonconforming use is changed to a conforming use, such use shall not later be changed to a nonconforming use.