No, I’d think they will try and keep their 20% stake. They have valuable work for Airbus and argubly they do some of the most hi-tech part of the work – the wings.
There is no reason why they would want to stop that, unless the competition authorities felt that it was unfair.
In a related story, BAE are supposedly looking to buy/merger with Thales, although Thales deny this.
One thing is for sure – they are keen to buy someone or be bought, whatever works out best.