25. The competent authority may at any time by notice in writing to a notifier—
(a)set a time limit for, or impose conditions with regard to, a particular contained use;
(b)require the notifier and any user to suspend, terminate or not to commence a particular contained use;
(c)revoke or vary a consent granted to the notifier under regulation 11,
and the notifier and any user undertaking the contained use must comply with that notice.