Yup, that job (simulator assistant) is an ATSA 2 post recruited only from internal candidates as the advert says. This is not a "blip driving" job. It covers a whole gamut of duties.
Importantly, the blip drivers are ACPO/ATSA 1's, the majority of which now are employed by Capita. Pace152 was interviewed for one of these ACPO vacancies, not an ATSA 2 job.
I say again, there have been no internally filled NATS blip driving jobs at PC so Pace152 must have been unsuccessful in his or her application on merit, or lack of, alone.