If 27s are in use then arrivals will be halted for a while before until all aircraft are out of the way. Aircraft will still be able to depart LHR. 09 ops poses more restrictions of course,
No other aircraft will be allowed in the London City or London CTR's from a set time before until after the flypast.
Obviously this means that there will be no City airport or Battersea movements either.
The formations will come in from their formation points over East Anglia under the control of Wattisham Approach and handed over to Thames radar.
The fact that it is a mil/civil formation matters not in terms of who controls the aircraft - just depends on who owns the airspace.
After overflying the formations will cotinue either north east between STN/LTN or overhead Benson for recovery to Brize.
Concorde will land of a visual approach/ILS straight in (if on Westerlies).
Is that OK?!