For all events, including, but not limited to overnight and stakes races, all drawings shall be final unless there is conclusive evidence that a properly declared horse, eligible at the time of entry, has been mistakenly omitted from the race through the error of the licensed racing entity, its agent or employee, in which case, the racing secretary shall immediately redraw the race in question, provided, that the error is discovered prior to scratch time or the printing of the program whichever is sooner.
7 Pa. Code § 205.330