I suspect this will open after February 1 2023

Seriously ATL has to have the highest number AMEX Plat and DL AMEX Reserve card holders passing through every day -- the ATL SkyClubs are already at or near capacity depending on time of day, I would expect no different with an ATL Centurion.

I wonder if they are going to take over one of the SkyClubs in "D" that DL is turning back over to the airport when they build their new massive SkyClub in D. Or if AMEX is going to share some of the costs with DL and locate the Centurion across from the new D SkyClub (DL is adding a brand new 3rd floor just for the SkyClub so it's possible they carve out enough space for both).