I take back my comments about the arrival lounge. It must have looked deceptively unfinished last week, because I just had another look and the furniture is all in now, they had a video monitor installed and being tested, a security room off to the left looked finished with CCTV cameras/monitors all working. The furniture still was covered in plastic, as was everything else, and the flooring had some protective covering. That can all be removed in a day and then maybe of week of check-out and tweaking before being ready to open. I'd give it two weeks based on what I've seen now.
As to the lounges on Concourse C, I asked the attendant on the one open (to your left as you go towards the gates) about the other lounges. She said the one opposite it on Concourse C will open next week and it is identical to the already open lounge. It looked totally ready to go already. She said the lounges on Concourse E will open sometime later, but didn't know when. She had no idea about the arrival lounge as she said the people for departure lounges and the arrival lounge are totally separate.