A cabin crew arriving BA31 on 22 September tested positive. No pax tested positive.
According to protocol, the other cabin crew should be isolated too. The pilots who did not have contact with that FA have been allowed to fly back but isolated from the pax.
I guess that this led to the cancellation of BA32 HKG-LHR departing 25 and 26 September as that crew was supposed to fly those return flights. Similarly BA31 on 24 september was cancelled.
Big mess. And BA will have a bad mark. It is very rare nowadays that cabin crew test positive
With the low traffic and to avoid the risk, some longhaul airlines have stopped flying to HKG (e.g. AF), KL makes a stop in BKK to have no crew overnighting in HKG.