As has already been mentioned, BASSA/Unite are effectively irrelevant and have been since the end of the last round of strikes.
New Fleet will start in the Autumn, so removing the previous crew from a tranche of routes (the list is out there) leaving a surplus of crew to cover the remainder. We know that no more than a couple of thousand will walk out, even if any new ballot (which may or may not actually happen) so the surplus will, to a certain degree, offset the number of strikers and the VCC will make up for the rest. There is no point in striking if it will have no effect.
Stupidity is the act of continually repeating an action with the hope of a different outcome (or something like that). A further strike ballot will not bring BA any closer to the negotiating table than it has been already simply because they know that a further strike will be even less effective than the last.
What grounds would a new strike be called over anyway? BASSA don't have many options to choose from to provide a suitable disconnect from the last action. No protection? Even less support. You've been warned.