On BA's approach, I agree BA is going to sit this out. It is somewhat ironic that DH now claims that the ballots are no longer about strikes, but "sending a message". It is for exactly this reason BASSA and CC89 implored their members to vote yes the first tine round nearly 18 months ago.
And collectively, through their representatives, cabin crew are enabling BA to do this by just sitting waiting for something to happen. If Unite was actually proposing new settlement offers, BA would have to entertain them.
Whilst I don't think there is any doubt there will be another Yes vote, it will be interesting to see if the Yes vote continues its downward trend:
1st ballot 9,514 out of 12,780 members
2nd ballot 7,482 out of 11,691 members
3rd ballot 5,751 out of 10,230 members
4th ballot 9,824 members to be balloted