Originally Posted by
canadiancow
Downgrade priority does not look at who's assigned to the broken seat. You're just more likely to be moved to some other arbitrary seat.
This happened to me once on AC, LAX-YYZ on 787. My business pod/seat was swapped about 6 hours prior to departure, and when I boarded my original seat was marked with INOP tape and seat cushion removed. F/A said it had been INOP on way from YYZ-LAX that morning as well. I ended up with a similar seat so I wasn't terribly concerned about it.