Mate thats the risk we all took to get the job. If you leave uni and go to CTC now you will have lots of debt. If you finish uni and then go to CTC/whoever you will still have lots of debt. You want to be a pilot so you are going to have to pay to get into the club however you choose to do it, unless you go via the RAF.
If you feel you can't wait then go for it, a mate from my course quit uni half way through his degree to go to NZ. Plenty of other guys did. Personally at your age I'd finish the degree, but thats just me. CTC won't guarantee you a job - they can't, but they haven't failed to place a cadet with an airline yet.