I would agree with Scuzi. I applied to NATS when everyone else in my year group was applying to university. Twelve years later, some of them are still not established in a career, nor do they really know what they want to do. That's not a criticism by the way.
Why not apply now? If you get in, great. If not, then you could go to university, and apply when you gain your degree.
I have no regrets about not going to university at all.