ARSD 20:04:28:29. Stewards to fill vacancies among racing officials

When a vacancy occurs among the racing officials, other than the stewards, prior to post time of the first race of the day or when a vacancy occurs after the racing of the day has started, the stewards shall immediately fill the vacancy. The appointment shall be effective only for the day, unless the association fails to fill the vacancy on the following day and notifies the stewards of its action not less than one hour before the post time of the first race of the day.