Grosvenor appeared to have a successful sale Jim Mullett collection of British Offshore Islands on 26th April 2012.
My highlight was a postcard sent by the infamous W. R. Bray, who was famous for testing the Post Office regulations to the limit for sending letters, cards, bicycles, etc. through the post. It was sent from London with the message that the card be forwarded around the British islands as fast as possible, and sent via Lundy, Beaumaris, Holy Island and Sandwich. Estimated at £100-150, the estimate was thrashed and fetched £550 plus commission!
Just spotted the same W. R. Bray card up for auction at Christoph Gaertner in June 2014. Estimate €500.
And it sold for €800 plus commission!