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The second picture may well be right, but I do not think that the first picture is the same species at all, is it?
Neither are families about which I know anything much at all, so wait for David Gibbs, perhaps.
My Flickr photos...
First shot a sciomyzid.
Second could be T.diaphanus, but I don't know how you distinguish this species from Phaonia pallida from a slightly blurred photo.
Lat/Lng: 51.23236, -0.3511
OS grid ref: TQ152494