(1) An Appellate authority may admit an appeal under section 43 after the period of limitation laid down in that section, if the appellant satisfies the appellate authority that he has sufficient cause for not preferring the appeal within such period.
     (2) In computing the period laid down under sections 43, 45, 46 and 47, the provisions of sections 4 and 12 of the Limitation Act, 1963 (36 of 1963), shall, so far as may be, apply.
     (3) In computing the period of limitation prescribed by or under any provision of this Act, or the rules made thereunder, other than section 43, 45, 46 or 47, any period during which any proceeding is stayed by an order or injunction of any court shall be excluded.