Hey Blizzard,
I am thinking to avoid the congestion of all of the threads discussing the downtime, maybe it’s worth changing your maintenance message to match the new expansion release message. If you say, it will happen on or before a specific time toward the end of the day on a very specific date no one can really complain. If it comes up early, everybody’s happy. If it goes all the way till 5 PM Pacific standard time then people were already expecting it. This way you can buy yourself some extra time and avoid all of those crazy little loopholes that people make up in their own minds. 
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