Thanks, Panic Stations. That seems to be the answer.

Whatever it was, it wasn't snow in Zurich - no snowfall there, just a few flakes. Bristol had more .

I feel a little guilty about this. I booked the flights and left my wife only just enough time to do what she needed. For whatever reason (lack of pilots?), she lost over three hours. At least her bag arrived.

Oh yes, after two hours a meal should have been offered, according to ba.com. It wasn't. But at least she used her 'no catering' voucher at Pret a Manger, so it wan't all bad news.