There are plenty of people out their flying airliners with poor educational qualification.
It seems to me that your path will be slogging away in the Instructing-Air Taxi-Turboprop route. Your advantage is your age. You can drop everything at a phone calls notice, move to the other side of the country for a job, live in a knackered old caravan on the rough side of the airfield, live off Aldi baked beans etc. etc.
On the random Thursday afternoon in 5 years time when you are in some hangar somewhere talking to somebody else they'll need a pilot with some twin time for 'a bit of work over the summer' an hey presto your career is off. They'll never advertise nor want to know about your GCSE's. You were in the right place at the right time with a license in your back pocket and the requisite hours in your logbook.
Good luck, it can be a fun and rewarding path. Beats being miserable in education for 5 years getting turned down for endless sponsorships, getting older and gaining commitments.
Good luck,
WWW