Charlotte, don't worry about missing this opportunity.
There's another one (a Ken Bird rather than a Bob Jackson) lurking in a shed in Forest Hill. Would you like me to pester its owner to dig it out and dust it down?
It still holds, I believe, the current tandem 100 mile record from around 1979 but I'm not sure how to check that.
I did once watch an attempt on the 200m flying start tandem record at Herne Hill. It was quite a spectacle, and they missed the record by a couple of hundredths of a second, I seem to recall.