BA should tell them just where to shove it.
I fail to see the point of negotiations at this late stage when so much damage has already been done.
Far better to let them have their strike, let the ones with sense, together with the volunteers crew as much of the operation as possible, sack the militants, then, when the strike crumbles the rest of us can get on with making BA a great company again - even with the BASSA cancer cut out it will be an uphill struggle but doable.