The problem is that during the big BASSA strikes BA did the same and removed pay and concessions. Then in order to return to some kind of normality rescinded this and there was no loss to crew.
It seems that the new management see this as weakness and will stand firm no matter what in order to send a strong signal to others who may contemplate taking action.
The strikes seem to be having very little, if any, real effect on BA so I guess they will continue to play hard ball.