Notwithstanding anything in sections 10, 11 and 13, the Assessing Authority may, at any time, subject to such conditions as may be prescribed, amend the order of assessment of market value and determination of tax in respect of any land or building where it appears that it is necessary so to do in order to bring it in accord with the existing circumstances and in particular may amend or correct the order as appears to it to be necessary by reason of- (a) the rate of tax having been altered under the provisions of this Act: or (b) any change having taken place in the ownership of the land or building except by way of inheritance; or30 (c) the land or building having become or ceased to be liable to tax; or (d) any building having been substantially damaged or destroyed or any building having been built, rebuilt or enlarged; the order so amended or corrected shall, subject to any order in appeal or revision, be effective from the commencement of the year following the year during which any of the events mentioned in clauses (a) to (c) take place and in case of clause (d), from the commencement of the year following the year during which such building re-building or enlargement is completed or such building or enlarged portion is occupied, whichever is earlier and in other cases, from such date as the Assessing Authority may direct: Provided that no order under this section shall be made unless the owner of the land or building has been afforded a reasonable opportunity of being heard and of producing evidence.