bmi diamond club - Misconnex on redemption ticket

So here I sit in IAD. Originally booked on UA948 due into LHR 07:30 and departing on BD52 @ 10:45 tomorrow morning.
Turned up having checked in onlike with all boarding cards ready just to check bags in and got an error on machine. We then found out flight to LHR is cancelled. We have now been put onto the UA924 scheduled to arrive into LHR at 10:10 and still have boarding cards and bags checked through to EDI on BD52
Now being positive I was thinking, ok we should make it and bags won't...fine. Now looking at the arrivals history of the 924 I think it very unlikely we stand a chance of catching our flight. I would have expected UA to move us onto the later flight as we are obviously under the MCT but we are where we are (sitting in the lounge)

So when we arrive bleary eyed with the BD52 probably having left...what do we do? what is likely to happen? should BD or UA sort this out?

many thanks for any advice

what do we do? what is likely to happen?Contact ground staff of UA upon arrival at LHR... Maybe they have you already rebooked until then...
should BD or UA sort this out?UA, despite BD would probably be more efficient in LHR...

thanks - just kicking myself as, if I had thought, I should have tried to see if they could have moved us to IAD-EWR-EDI but nothing was even suggested apart from puting us on the later flight...and the earlier flight is also still here "awaiting aircraft"..don't know if this is the norm but is seems rather chaotic here (the CDG passengers have been told their aircraft cannot go TATL so will take them to EWR then they will swap planes)

So when we arrive bleary eyed with the BD52 probably having left...what do we do? what is likely to happen? should BD or UA sort this out?

UA agents meet flights at LHR. Explain to the agent at the gate / door. He/She might well already be aware and have plans.

If no luck You're connecting within T1. Follow signs for flight connections and you end up back in T1, and near the Star Alliance lounge are desks. There are UA and BD separate desks so you can approach both / split up for the shortest queue.

Is there precedent for rebooking onto BA flights since the takeover?

Nevertheless it's good to see no jungejets in sight, so hopefully there will be capacity on the later BD flight.

BD 52 10:45 AM 319
BA 1442 11:40 AM 319
BD 56 12:15 PM 320
BA 1446 1:20 PM 319