Strangely this is only showing 21 and 22 cancelled, mine was cancelled and it's later than those dates.
https://www.flightradar24.com/data/flights/ba154

The way the passengers behaved on my flight over on the 17th due to the aircraft downgrade I'm not surprised they chose to cancel... it's a threat to staff from some of the behaviour I saw, which makes me side with the earlier post that's the real reason.