But the question is whether BA have the right to do what they did.
And the answer is yes they do - until or unless the courts decide otherwise. That's how it operates, you can do whatever you like until the legal system (or Parliament) decides otherwise. In all honesty, continuing to go on about it is pretty pointless, they can and have done it. At some point in the future it may be decided they couldn't, but as of right now, they can.