Hi,
NATS no longer have a requirement for A Levels for there trainee ATCO positions.
According to the website, theY require five GCSE's at C and above. And obviously the passing of the selection tests and interviews to be accepted!!
NATS new wannabe ATCO website will tell all in more detail -
Welcome to NATS - Jobs and careers at NATS
Hope that helps - good luck with the application, I'm at stage one for the second year now!
GavReal