23. The replacement of a contestant listed on the program of a sports event shall be authorized by the board at least 24 hours before the beginning of the first bout. The board shall permit such replacement where the substitute contestant is declared medically fit to fight by a physician designated by the board and where he already holds a licence issued by the board or by an athletic commission or a similar government-established agency. In the latter instance, the board shall issue to the substitute contestant an annual licence in accordance with the Regulation respecting combat sports licensing (chapter S-3.1, r. 7).