Yes, and in my experience they do, but only in exceptional situations. Had it done just a couple of months ago. Had to speak to a DM supervisor who, after putting me on hold for about a minute or two, came back with a confirmed Z seat on a pretty heavily booked medallion-heavy flight. Was not an IROP situation, but there was a DL ticketing error on a complex itinerary. I suspect they would not have done it otherwise.