Yes, I used to be a member of that group about 25 years ago; they used to meet in Staines IIRC. The nearest group to me now is Herts, but it's 50 miles to where they meet up before a ride out and I haven't been able to make it for over a year since I rejoined - need a trailer really.
I used to ride around Maidenhead and Knowl Hill regularly, but the RUPP's (as they used to be called) are all RB's now!
I intend on doing some research of the Bucks area soon; if you are close to me, maybe we could arrange a ride out?
Not may lanes in Bucks I'm afraid. There are a few South of Princes Risborough totalling about 2 miles, one graded one in Chesham, a very small lane at The Lee near Chesham, and that's about it! The rest have become RB's or got permanent TRO's.
I have to travel to Herts, Beds, Essex or West Berks and Wiltshire to get to any decent lanes.