[Margaret Pilkington]

No, Neil. Surgeries used to provide their own out of hours service in the dim and distant past.
The doctors worked on a rota and went out to see their own patients who needed the services of a doctor. It is a long long time since that happened. Now if you call a doctor out of hours you can get anybody.
It could be someone from a practice in Blackburn, it could be someone who has flown in from Germany for a lucrative weekends locum work...but what you can guarantee is that they will know nothing of your past history, other than what you can tell them(and with some members of the public that is worse than knowing nothing at all)

I would hazard a guess that your practice is the Rhyddings Surgery.
You are right on all counts it IS one of the better ones...The GPs do not seem to be driven by money...but they could manage the hours of opening better by staggering lunches for staff.