It isn't just Cranwell that can chop you, 20 years ago (
) I went through Swinderby (like 6 weeks of cadet camp), 7 weeks of Finningley AAITC - Bloomin hard (for want of a better word) 12 weeks of ALM Basic Groundschool (fun) CSRO training, then Rotary ALM ground school (forget half what you learnt for Hercs) and then onto the mighty Wessex at Shawbury.
I then relaxed and enjoyed myself far too much, got into a few scrapes and then was told that I would fail my flying course on my behaviour.
I was back-flighted and did it all again, but 2 days before the end was chopped from flying for good due to my 'Personal Qualities'.
I then spent some quality time working for the SWO at Shawbury before doing an attachment in PhysEd at Brampton before finally going to Innsworth to be offered a choice between Steward, ATCA and a couple of other not particularly enticing trades, or I could leave. I took the latter.
Moral is: You can be chopped at any time they see fit, so if it is what you really really want, then go for it, keep your nose clean and work hard right the way through to your brevet.