Thanks for this link.

I have a return flight booked from France to JFK in October (AF ticket, Delta operated flight), and the Delta site does allow me to upgrade to Comfort+, but at a cost of EUR 81 / passenger. I have a Platinum for Life card.

Air France has a team specifically assigned to Delta ticketing, and they are not aware of the information on that news page. The lady I spoke to was not able to give me Comfort+ seats.

I would be curious to know if anyone else has actually been able to reserve a Comfort+ seat free of charge at the time of reservation? And if so how?