(1) The Municipal Commissioner or the Executive Officer may, at any time during the erection of any building or the execution of any work or at any time within three months after the completion thereof, suo-moto/special complaint or during inspection, by notice, in writing, specify any matter in respect of which such erection or execution is without, or contrary to, the approval referred to in section 427 or is in contravention of any condition of such approval or of any of the provisions of this Act or the rules or the regulations made thereunder and require the person who gave the notice or the owner of such building or work either –
(a) to make such alterations as may be specified by the Municipal Commissioner or the Executive Officer in the notice with the object of bringing the building or the work in conformity with such approval or such condition of such approval or the provisions of this Act or the rules or the regulations made thereunder, or
(b) to show cause, within such period as may be stated in the notice, why such alterations should not be made.
(2) If such person or such owner does not show any cause as aforesaid, he shall be bound to make the alterations specified in the notice.
(3) If such person or such owner shows the cause as aforesaid, the Municipal Commissioner or the Executive Officer shall, by order, either cancel the notice issued under sub-section (1) or confirm the same subject to such modifications as he thinks fit.