340.254.  Existing certificate recognized, requirements. — Any person holding a valid license, certificate, permit or other authority regulated under the provisions of sections 340.200 to 340.330 on August 28, 1992, shall be recognized by the board and shall be entitled to retain any existing status so long as the person complies with the provisions of sections 340.200 to 340.330 and board rules promulgated pursuant to sections 340.200 to 340.330.