Well this was a random find in an Oban charity shop yesterday, a program for the 1981 Falkirk Tryst Bi-Centenary Piping Competition, signed on the back by eight of the participants.
It has a chronological history of the Highland Society of London's competitions from 1781 but no mention of bellows pipers not being allowed to compete or two drone pipes being discouraged. :)
Another detailed MusicBrainz instrument tree fleshed out - this time bagpipes/dūdas/gaida, etc etc… untangling different but similar instruments from around the world is very interesting and very complex, it turns out!