Many moons ago many took commands in Scotland - not only more money but there were various allowances to move which meant a substantial saving on moving upmarket when they came back to London but most of my mates stayed put and excepted 20 years to command..bid line didn’t come into it.
SR had a much better system in that one went through short haul to medium haul then long haul and back onto short haul for command. Pay was equal whatever fleet you were on and trips were equalised rather than the senior guys pinching the best ones.
It was happier and better remunerated than BA at Heathrow although the guys who went to the DC10 at Gatwick had fun.
There was also the offer of unpaid leave on top of our 47 days leave.
One of the questions I was asked by the Swiss repeatedly was why are British unions so militant; my answer was because of management and their behaviour.