Looks like HG briefly touched just under 4,000 middle of the night.
Weekend is starting. So the CCU might hold up, or even go up a bit. But next week when Steam gamers get back to normal weekday gaming, it'll drop more.
Yesterday, the range was 4,000 - 10,000. So expect next week it could drop to 2,000 - 5,000 at some point. No doubt 3,000 - 8,000 should be in the cards at minimum. The trend has been a steep -30% or so each day. But at some point it should stabilize a bit if there's enough hardcore gamers sticking around. Comes down to how many of them there are to keep the CCU up to a certain baseline.