Thanks all!

I've definitely had a booking confirmation email, and I can see my booking in the BA app on my phone. I've entered Advance Passenger Information and got a "booking updated" email about that. I definitely didn't use avios by mistake (I didn't have any to use). I searched FT for the route in question and it seems nobody else has said anything about it. I'm not sure how to establish the fare code, but as far as I can tell it's just a normal economy class ticket.

All that said, I wouldn't be heartbroken if BA cancelled my booking. I was resigned to paying through the nose as it's in the school holidays, so if I end up having to do so after all, I haven't lost anything. If nothing else, it would be rather amusing given the bad press they got after the TLV cancellations and their public pronouncements about this sort of thing being "exceptionally rare". I guess if they are going to do so I'd just like to know about it now rather than in a week or two weeks or three weeks!

As a couple of people have suggested, booking a hotel with free cancellation is probably the wisest thing to do. Booking.com here I come...