Last vacation, no confirmable upgrade space so had to wait for the upgrades to clear one by one (last one didn't), so our 4 bus seats were almost as far as they could be from each other. Looks like we'll be playing upgrade lottery again next summer. Is there any reason why we should book even 2 pax on the same PNR? - I am assuming this might delay upgrades as we have to wait for 2 to become available.

In irrops, could they insist on putting us on different flights if we are not on the same PNR?