In the UK that kind of service is known as a "coach" rather than a "bus" generally.
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!
It’s £1.50-that’s the price!
So technically the ticket price can be as close to £1 as you want it to be.