The phrase "to upgrade another seat" means improving or enhancing someone else's seating arrangement, often by moving them to a better or more comfortable seat. Full definition
With the GT comes the V - 6 engine, 17 - inch alloy wheels, twin - piston front brake calipers, rear disc brakes, side air dams and upgraded seat fabric. (articles.orlandosentinel.com)
Whether you want to upgrade your seat on a plane or your room at a hotel, it can be possible with the right credit card. (rewardexpert.com)
The driver and passengers will sink in to new upgraded seats with more cushion material and be able to pick from new leather and cloth seating options. (media.fcanorthamerica.com)