(1) An appeal to the commission chief executive may be started only by giving the commission chief executive a notice (an appeal notice) stating--
(a) details identifying the decision appealed against; and
(b) reasons for the appeal.
(2) An appeal notice must be given and actually received by the commission chief executive before 5:00p.m. on the day that is 21 days after--
(a) for a promotion decision--the day the decision is publicly notified; or
(b) otherwise--the day the appellant received notice of the decision appealed against.
(3) However, the commission chief executive may at any time extend the time for giving an appeal notice.