Finally got to Palma on Wednesday ... 3 days late.
Sunday : Cancelled due to Mediterranean weather.
Monday : Cancelled due to ATC issue.
Tuesday : No more seats available.
Wednesday : Finally.
It does point to a significant downside, which never really struck me before, in using scheduled carriers to holiday destinations (generally at much higher prices). If you go with say Jet2 from Stansted, then although there may be a long delay and you get away at midnight, at least you get away. They rearrange, charter in from Titan, whatever. But go with BA from LCY and if there is an issue, it's just cancelled and you are back to the reservation system for whatever it has left. They may go daily, but a cancellation pretty quickly fills up what is left. Nor are you just sent emails with a phone number to rebook, which is just playing a recording that they are too busy, try later.