If a licensed trainer is to be absent from the track where employed, the presiding judge shall be immediately notified in writing and at that time a licensed substitute trainer, acceptable to the presiding judge, shall be appointed to assume responsibility for the horses racing during the absence of the regular trainer. The name of the substitute trainer shall appear on the program if possible. The presiding judge shall be advised immediately when the regular trainer is present and resumes his duties.
58 Pa. Code § 183.271