BA has very strong in-house legal capability (15 people in its in-house legal team), and they have used employment law specialists (John Evason at Baker & Mackensie) and Timothy Brennan QC to represent them in court on this case (who according to the quotes below conducts "lethal cross-examinations" in court).
Devereux Chambers | Timothy Brennan QC
I would be amazed if BA hasn't carefully checked that it has a watertight case on this.