As of Monday, Ric Flair still had not been to Pittsburgh for WWE's medical tests that are required before he can be brought back as a regular on-air talent.
One source believed that Flair could still be dealing with the blood clot in his leg. WWE doesn't allow their active performers to use blood thinners so that could be a problem. For what it's worth, it was mentioned in Flair's new interview with Mike Mooneyham that his blood clot issue had "cleared up."
As noted, Flair was backstage at Tuesday night's tapings in Atlanta but we haven't heard an update yet.