Hi TicTac1982
My advice would be along the lines of Straightandlevel80kt. Exhaust any opportunity up to the age of 26 to gain sponsorship. Why borrow £35K now when there is a chance (albeit slim) that you can follow a preferential route? Just a thought, but at 21 and with (I assume!) no ties, why not look at the forces if it is flying that is your dream?
From my own background, I too have always wanted to be a pilot but had to put it to the back of my mind during my twenties (just no way I could have afforded it). It is only now (32) that I am about to embark on a fATPL, but with one difference, I am a fully qualified accountant. The thought that you have something to fall back on is massively comforting, and conversely, something that a potential employer may see as separating you from the others in a positive way. You have to be able to offer something that the hundreds of others don't.
As you are young (and believe me, you are!), this may seem like a total waste of time, but look at gaining another profession (and I'm not just pushing accountancy here, but the world will ALWAYS need accountants) in the meantime, while pursing those elusive sponsorships and gaining a PPL. Do anything, but give yourself something to fall back on. You have time, use it wisely.
Crikey I sound sensible for someone who is soon to borrow/spend an awful lot of money!
Seriously, best of luck to you.