Stopped by the ATL AC last week. The staff (as well as I) have no idea of why this club is not reopen to guests. The staff said they have no shortage of members coming into to see if the club is open. Furthermore, they've now been told there's no definitive date for re-opening. They understandably complained of boredom and not have passenger interaction.
To their great credit they have coffee to go. Also, after I left the club one of the front desk members sought me out in the terminal. She put me on an earlier flight leaving for CLT in about 10 minutes that had open seats in F.