Originally Posted by
luitje
1. She shall be claiming refund through her TA
2. EC261 compensation shall be claimed directly to BA, using their web-form.
3. I understand BA is not be liable for the cost of alternative flight she had to take.
1) Correct. Under the Regulation it is strictly speaking BA's direct responsibility, but in practical terms it is best to see an Involuntary Fare Refund from the TA, which should be half the return fare if that was what was purchased. If the TA won't do that, then you can approach BA.
2) If the flight was cancelled yes she can apply via the webform. If the flight was delayed she isn't able to claim compensation if she wasn't on the delayed service.
3) Correct, as things stand. This is open to argument, depending on details and circumstances, but as things stand, if BA offered her an alternative routing and she declined it then BA isn't liable for the alternative arrangement.