Hi Adam
Theres nothing stopping you at all doing your PPL abroad and your hour building then returning to the UK to complete you CPL/IR flying.This is the path I'm going along myself as I already hold the PPL I'll be returning this year to hour build up to 150-160 hours then pick either Oxford or cabair for my CPL/IR training.With the full time gound school to obtain fATPL.
Regards Gavin.