Since it got mentioned earlier on every time I taxi past Terminal 3 I notice more and more Delta aircraft at the gates and less Virgin Aircraft. I get the feeling Virgin is expending at places like Manchester and Gatwick but shrinking at Heathrow. Since I don't work for Virgin this is just an observation. Is it a correct observation that Delta has taken over quite a few of the Virgin slots at Heathrow or are they just covering the slots because of the ongoing 787 engine problems?