IRROPS and international award ticket involving star alliance flights
 

I have an upcoming trip that is a business class award ticket that involves a transatlantic united flight followed by an intra european brussels airline flight ... (all on the same 016 award ticket, all seated in business)
What happens when the eastbound evening transatlantic flight is delayed by several hours (for bad weather like what happened today) to the point of missing a 3hr connection in Brussels ?
I would guess that if it was a paid united ticket then united (016 ticket) (or is it brussels airline ?) would reaccomodate you on the next available flight ... and I would expect they would reaccomodate in the same cabin as ticketed unless you agree to a downgrade ...
Is there anything different in the context of award tickets ?
how automated is the process to rebook (mix UA and star alliance partner) ? does united attempts to do anything proactively once they know the connection is going to be missed ?

No ... especially in this case. If UA delivers you late, UA is responsible for getting you to your destination even if they need to buy you a cash ticket.

Occasionally partner creating a misconnect on a UA award will make noise about need award space, untrue but it may some pushing in that class but it is what should happen.

Thanks for the clear answer ...