esudfu,
stage 3 is tricky, there's no denying that. But you have been given a lot of good material from NATS; they do acctually say exactly what they're looking for. Use that and study it.
My Heathrow visit was great and I'm sure your's will be aswell. Take your time to ask questions and talk to them as they're all very helpfull. I also found that the LPOs (you'll see what they are tomorrow
) in general seemed to have a bit more time to explain than the ATCOs and they're very good at it too so make sure to ask them. If they don't know they'll just have you ask an ATCO instead (which isn't always easy because they do tend to get quite busy
).
Have fun, I hope you learn a lot and then just do your very best. In the end my best advice for stage 3 is the same as for the other ones.
Sleep well.
Proper breakfast.
Do your very best and try to relax.
Good luck
