Ah, I can breath a sigh of relief. We're not going to be treated to a local Bluetail after all but it at least appears to have been a genuine mistake (I think?) and was a mix up with a photo of the Gloucestershire bird.
I just hope my pessimism is proven wrong in fantastic style with a reappearance for the birding hordes; otherwise what little hope I have for birding will erode in another great big chunk like an east coast sea cliff.