After March 17, 1948, any insurer may file with the Commission a written notice of its election to comply with the provisions of §§ 38.2-3202 through 38.2-3213 after a specified date before April 1, 1948. After the filing of the notice upon the specified date, which shall be the operative date for that insurer, the sections shall become operative with respect to the policies thereafter issued by that insurer. If an insurer makes no election, the operative date for the insurer shall be April 1, 1948. The Commission, for good cause shown by any insurer, may extend the operative date for that insurer to not later than January 1, 1949.