Spotted bathing in a pond in Surrey, good view, but no time for photo. It should not be here, but I cannot think what else it could be? Definitely not a collared dove or sparrow hawk or kestrel. We do hear a lot of cuckoos here in season.
The simple answer is almost certainly 'no'. Some birds do occasionally winter here, when they should be in warmer climes, but I have never heard of a cuckoo doing so. The normal confusion species for Cuckoo is Sparrowhawk, as they both have barred underparts. Male Sparrowhawks are the same size and a similar colour above, with a barred underside and a long tail. They are superficially very similar and often confused. That would be my guess.
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I see Sparrowhawks almost daily, so should certainly have recognised one at that distance. But I suppose the bird's feathers would have been "ruffled" for bathing and the angle was unusual, so maybe you're right. Such a shame there was no time to take a photo. It would have been an amazing spot if it was a cuckoo!