Originally Posted by
DownUnderFlyer
Of course you can leave the airport. I think what QF means is that you can't leave the airport once you have gone through immigration and security.
No, they mean you can't leave the airport. I have been told exactly the same thing myself after checking in ~5 hours early for a PER-SYD flight ("I'll check you in now, but you're not allowed to leave the airport").
Obviously, they have no way of actually
enforcing this, but it is (apparently) one of the "rules".