Can you help to identify these frames, bikes or parts?

Anybody got any idea about Geoffrey Butler bb stamps? Got a nice frame with Geoffrey butler decals and the bottom bracket is stamped LB and -7. According to the stickers the tubing is 531 st. Has full touring mounts as expected.
Lugs are extremely similar to this bike:
http://www.lfgss.com/thread33976.html

But with concave bits where the seat stays join the top tube, like this:
http://farm8.staticflickr.com/7243/7233284120_9e86f85dc3_z.jpg
Frame looks in pristine condition, stove enamelled with no chips at all just very slight cable rub on one patch.

I don't doubt it's a Geoffrey Butler, but the bloke who sold it to me said it might have been built by Cliff Shrubb. The guy seemed nice and used to race with one of the Swinnertons, very interested to see if he was right about Cliff Shrubb.

Built by Nigel Dean, called up GB and they were very helpful.
It was built in the early 90's and is the same frame as the lovely Nigel Dean Tour Ace frames.