What you don't seem to be taking from this is that , nats has always been a first come first served organisation. Now apparantly a decision has been taken allegedly by management that allegedly allows one airline priority over all others operating into britains biggest airport.
AND if this a/c does get priority when eats are inforced then it is not just one minute it is the two a/c slots that it takes on final approach ,in lvps for example, that could have been your slot, and yes after holding for forty minutes at ockham to be told at your eat that you have to hold for another five minutes could mean that your 747 is diverted to manchester!
This, procedure is allegedly so sensitive that the atco's involved have been told not to mention it on the r/t or on tels. That is why they aren't talking.