1. The game is released on the 27th for EVERYONE ... and that's because we only have one way of specifying a date/time for everyone (UTC). Blizzard themselves has stated it releases on the 27th ... at 12:00AM on the 27th.
2. All precedent is gone ... the PVP announcement precedent and the prepatch precedent can no longer both be true, unless the precedent of releasing the expansion on the announced date is itself gone.
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Firstly - if people meant 'the fall of civilisation' - they may still be correct
But seriously - isn't Fall 'Autumn' and doesn't the US have a bizarre idea of not starting seasons until they were half way through - so isn't the 15th of December 'Fall' in the US.