Permission of the Municipal Commissioner or the Executive Officer to be void in certain cases

Any permission under section 171 shall be void,- (a) if the advertisement contravenes the provisions of any regulations made under this Act, or (b) if any material change is made in the advertisement or any part thereof without the previous permission of the Municipal Commissioner or the Executive Officer, or (c) if the advertisement or any part thereof falls otherwise than by accident, or (d) if, due to any work by the Central Government, the State Government, or the municipality, or by any statutory authority, the advertisement is required to be displaced.