Classicwings: Don't worry, you'd have the same opportunity to join NATS as an ATSA at Newcastle as anyone else would under the current regime. If you were good enough to be trained by NCL as an ATCO, the same will apply regarding your chances of getting a Cadetship with NATS, if you aren't it won't happen.
Goatface, I intend to bypass the ATSA route - and then be put forward for a cadetship - altogether, by appearing for consideration at Newcastle with my self funded ADI rating. This is subject to whether the unit is still managed by NIAL of course. And yes, I do have previous practical experience with my FISO licence.