BOS cancelled yesterday, so they probably couldn’t afford two cancellations in a row on that route.

Trying to ascertain any sort of pattern with the cancellations is pointless (I’ve been trying to do so myself for the BOS flight, with a booking coming up later this month, and there’s nothing discernible as a pattern in there).

I’m not very sympathetic to BA at this point. The A380s have been back for long enough - they need to advertise a schedule they can operate reliably.