All of CO's announcements on increasing the number of FC seats - like on the 753, and 738 and 739 - have highlighted that this provides better opportunity for Elite upgrades.

The net is that on the 738 and 739 - CO is adding 2 FC seats and not changing the number of coach seats. Hence, whether they sell those 2 extra seats (which they can on a transcon) or upgrade two Elites from coach and then can sell 2 more coach sets - the net is an increase in revenue.

CO is also adding 2 more BF seats on the 777 (48 to 50) with changes to the entertainment system. Then net is two more revenue seats.