Mr 187 - How many flights per day do BA have to your destination? Less profitable routes will go before more profitable ones ... routes with multiple flights per day might well get some consolidation.
A target of 100% Long haul means just that ... a target. No guarantees. In fact no airline will be able to guarantee you get away that day as the aircraft may have technical issues \ there could be weather delays etc. But you are taking an additional risk with the strike as well and, personally, if you have to fly that day then I would look elsewhere. Nobody on here knows anything yet and won't until after any strike dates are announced so asking on the forum is, sadly, pointless.
Ultimately it is your call. You have to live with the decision.