I'm not going to join in the assorted bashing exercises, because I know not enough about the facts. I'm just a paying punter in this context, who isn't flying MaxJet any more, for well-known reasons.
However ... I'm booked with BA, LHR-IAD, in about 8 weeks' time.
Notionally a T5 departure ... is that likely to happen?
Or is the "remain at T4 for now" [another Hell-hole] option more likely?