Well I got this back yesterday afternoon. ...which is fair enough. Clearly they oughtn't to tell me about currently ongoing investigations etc., but I just hope it was tracking physically dangerous people, rather than thermaling people's attics - although I can't, of course, expect the Police to agree with me on that one! To my great relief there was no repeat last night (not until I was already fast asleep with earplugs in). And now for my next windmill - Southern 'Trains'...