s 226HC Non-renewal or cancellation of third party BPD warrant
(1) This section applies where a third party BPD warrant ceases to have effect because it expires without having been renewed or because it is cancelled. (2) The head of the intelligence service to whom the warrant was addressed must, so far as is reasonably practicable, secure that anything in the process of being done in reliance on the warrant stops as soon as possible. (3) Nothing in this section affects the lawfulness of— (a) anything done in reliance on the warrant before it ceases to have effect; (b) if anything is in the process of being done in reliance on the warrant when it ceases to have effect— (i) anything done before that thing could be stopped, or (ii) anything done that it is not reasonably practicable to stop.