(1) The Appeal Commissioners may accept a late appeal where -
(a) they are satisfied that -
(i) the appellant was prevented by absence, sickness or other reasonable cause from making the appeal within the period specified by the Acts for the making of that appeal, and
(ii) the appeal is made thereafter without unreasonable delay, and
(b) the appeal is made within a period of 12 months after the end of the period specified by the Acts for the making of that appeal.
(2) Notwithstanding the period specified in paragraph (b) of subsection (1) for the making of an appeal, the Appeal Commissioners may accept an appeal made after the end of that period where paragraph (a) of that subsection applies and -
(a) any return that was required to be delivered to the Revenue Commissioners under the Acts has been so delivered, and
(b) the requirement in subsection (3)(a) or (b) (or both as the case may be) has been complied with.
(3) Each of the following is a requirement mentioned in subsection (2)(b
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