Well, here we go - just 20 minutes from the start of the update window. All we have is "evening" and "after 9:00 PM".
Evening seems to basically start at 5:00 or 6:00 PM, but the ending of it has a lot more variety. Some will say till "night", or after sunset, but often it is defined as until bedtime - which varies a lot! For Mark, you are probably looking at 3:00 AM! At least based on when some phone calls have ended, or prior posts have been made.
So essentially a 6 hour window. I suspect he doesn't even get home until 8:00 or 9:00, again, based on some phone calls. Of course, they could be exceptions to his schedule. But it seems likely the update will come after he gets home. Which leaves the question of whether it is pretty much ready to go with just some final touches or will it be written from scratch after he gets home. If the latter, I expect an update wouldn't come too soon after 9:00.
But I'll be up and waiting since even 3:00 AM is only midnight here.