If I remember it used to update around 11:00pm PST. Everyone complained so then it was bumped to 1:00am(?) PST. It wasn't a big deal since it usually only lasted 15 minutes or so.
Now the problem is it usually goes down (can't load anything) just after 12:00am PST. It usually doesn't come back up until almost 2:00am. That's almost two hours of down time where the forum isn't even accessible. Something doesn't seem right to me?
I have noticed it too. Later at night and longer than usual. It isn't up to really, it is the hosting site that determines when, why, and how long the updates last.