Great this all ended well.

I was surprised to read comments where people believed the flight would not have left london if the crew went out of hours dpwn route.

That is not my experience. This board will remember the relatively recent 872/873 krakow rotation tgat i predicted would leave london then overnight in krk, which is what happened on that occassion.

while i was not directly involved in that flight, i was on a lhr,-waw rotation that had a 3 hour ground delay at lhr with us all on board. The aircraft was supposed to return that but again overnighted in waw.

So i do not think it is clear that the aircraft would not leave lhr