Any permission under section 139 shall be void,- Permission of the

Chief Municipal

1. (a) if the advertisement contravenes the provisions of any regulations made Executive Officer under this Act, or Municipal Executive
2. (b) if any material change is made in the advertisement or any part thereof Officer to be void in without the previous permission of the Chief Municipal Executive certain cases. Officer/Municipal Executive Officer, or
3. (c) if the advertisement or any part thereof falls otherwise than by accident, or
4. (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.