(3) No order shall be made under sub- section (2) after the expiry of two years from the date of the order sought to be revised. 1[ Explanation.- In computing the period of limitation for purposes of this sub- section, the time taken in giving an opportunity to the assesses to be re- heard under the proviso to section 38 and any period during which any proceeding under this section is stayed by an order or injunction of any court shall be excluded.]