(1)The Highway Authority may cancel any permission granted under section 21-(a)if any rent or charge is not duly paid,(b)if the purpose for which the permission was given has created to exist,(c)in the event of any breach by the holder of such permission or of any terms or conditions of such permission.(d)if the land on which such encroachment has been made is required for any public purpose or such encroachment is causing impediment or danger to traffic.
