18.—(1) Any licence issued under this order may be revoked or varied by the issuing authority and may be issued subject to conditions.
(2) A licence issued under this order shall accompany whatever is being moved under its authority and the owner shall, on demand by an inspector or constable, produce the licence to him and allow him to take a copy of or an extract from it.
(3) The authority issuing a licence authorising a movement shall with all practicable speed send a copy of the licence to the local authority to whose area the movement is authorised.