I assume what you are talking about is going to CTC or Oxford as a self sponsored student not affiliated with an airline. So the first thing is, have you considered waiting for the next chance to apply for the BA future pilot programme? See
British Airways Future Pilot Programme
I recently met a student who had just graduated from Oxford. He had applied for and subsequently failed the Ryanair selection. He said you only get one chance at Ryanair and as such he was basically without any hope at the moment as Oxford were unable to offer him any help. He'd sent applications everywhere and heard nothing. Others will be better placed to comment but it sounds to me that if you are a self sponsored student at Oxford with no airline involvement in your training, it is Ryanair or bust at the moment.
CTC on the other hand will place you in their holding pool once you finish training and the chances are you will eventually get a flexicrew contract working for easyJet. You might get lucky and only have to wait a matter of weeks, others have waited months/years. It really depends on the market when you graduate.