13.—(1) In the case of a penalty appeal, the notice of appeal shall not be valid unless it is sent to a Commissioner within one month of the decision of the appeal tribunal being sent to the applicant.
(2) For all other appeals, a notice of appeal shall not be valid unless it is sent to a Commissioner within one month of the date on which the appellant was sent written notice that leave to appeal had been granted.
(3) A Commissioner may for special reasons accept late notice of appeal.