Twin buzzing Buck House?

[Icare9]

twin Piper or Beech just (12:03ish) fairly energetically buzzing around what looks to be Buck House area. Dark blue tail. 2 circles from west to northwards then off to what I assume would be Northolt.

Anyone know if any commemorations etc for such an overflight?

[Hirem J Trashcan]

It's HER birthday today
Many Happy Returns, your Maj !