I remember way back when the Megabus from Edinburgh to London was the same type of bus as the one I used to go to school on :) And it cost 1 quid (plus 50p booking iirc).
Also, for GP, afaiu, the rules in Scotland are kinder (includes long distance) https://www.transport.gov.scot/concessionary-travel/60plus-o...
P.S. Hi Andy!