I know Comet don't offer any such 'schemes'.., BUT if you do hit a 'glass ceiling' in any of the establishments you may work for, give a thought to applying to Comet.
Say you were a manager at Sainsbury's for example; because of your management experience you can transfer to Deputy manager of a Destination store (big store of Comet) and be earning quite well and in Comet sky's the limit with prospects.
My ex-deputy manager went to college and did music technology for 6 months, lazed around for 6 months, then got a job at Comet as a Sales adviser...
A couple of years later was a Sales manager, then Deputy Manager now he has his 'own' store in Essex. I've heard of the similar sort of thing happening with an Area Manager, he did have A-Levels though.
Comet is always expanding with new stores opening every year, and recently Kesa Group took them over and they're (I think) part of the biggest electrical retail company in Europe. I could go on for longer, but I don't want to sound as if I'm trying to inspire people to buy stock..
I agree with the idea of doing a part-time degree as well. Even though you might want to go straight into work, if you did hit a glass ceiling where you needed a degree to break through then doing a part-time degree would be a good idea, and higher education has intrinsic value anyway!
Hope that helped a bit.