Wow I do hope our identification is correct. We saw the bird perching on a rock, the way it held itself it reminded us of a thrush, it was a bluey grey colour with black tail feathers which really stood out from the rest of the birds colouring. We didn't think it was particularly spotty, but were a few feet away from it, the bird flew off at quite low level again as a thrush might. I would say it was the size of a song thrush, but perhaps a bit slimmer. We saw it quite clearly. If it is of any use to you the map reference on OS Explorer OL 28 was 536 853.
After looking at our bird identification books and not finding anything else similar I then researched Blue Rock Thrush on the web I am sending you a link to the bird that looked identical to the one we saw http://beauquenne.oiseaux.net/monticole.bleu.4.html#monde. Note the black tail feathers which stood out so clearly on the bird we saw.
Keep me posted will you with your thoughts if it could have been anything else.
Look forward to hearing from you"