I'll do some digging....Spent a lot of time at the Beeb, still have a few contacts..Any more specifics would be nice, If it was recorded on 1986, there's a good chance that it's safe in the Archive! It was the 60s/70s stuff that got wiped...
If I ever see something of interest on the Beeb, I instantly zap it it onto my hard drive....Delia Derbyshire anyone?
(The Lady what wrote the Dr Who theme!)