Hi Tim,
One resource I have not seen mentioned is the Honourable Company of Air Pilots.
https://www.airpilots.org/
They offer flying scholarships (now closed for 2022) most years for a ppl (they also offer gliding scholarships). Competition for a place is intense. They also offer an airline evaluation course, where you are interviewed by experienced airline pilots and they suggest if you are likely to have the right abilities to succeed in the airlines. If not, this can save you considerable time and money. I think the course is either low or no cost to the applicant.