Update
Ok, to be honest they did a pretty good job. People transiting Japan, me included were taken off first, given a hotel voucher for the hotel airport and where applicable, told of our new connection flight in the US.
So now I’m on the bus to the plane and hope to get to DC at 13:30 so 13 hours late.
So overall JAL made the situation as good as it could be so a well done is in order