What day did you get back to LHR on the BA flight? The first available flight on QF was 17 days after my flight was cancelled. I'm wondering that was why you did not have an option to come back on QF because they were full?

The thing is though that you were booked on a QF-operated flight that was cancelled, so I assume that's why BA has decided to pass it onto QF. I'm not necessarily saying that BA's action is correct, but maybe they do have an agreement that the operating carrier deals with this.

FYI, QF is offering to refund up to AUD 300 equivalent per day per passenger in hotel and meals, although they, at the time, said passengers would get nothing from them because it was not their fault.