A330's
The beauty of having flightradar24 and such makes tracking of some aircraft fairly easy.
The A330 mentioned is currently descending into one of the Gulf airports having left Brize (per the trail).
Outbound earlier this morning from one of the gulf airports was an A300 although not sure where this is going. Another A300 is showing GOI-MAN due 17.15 and the other two on ski flights.
So it seems one A330 and one A300 are in and out of Brize at present. I have certainly noticed the A300 inbound Brize this week and the A330 has been all over the shop but the latter seems to do mainly IT work such as Goa's with a little dash of MOD work as well - source flight.data24.com.