IGN can confirm that servers for Fallout 76 have opened up a day early, and those who have it pre-loaded on PC or have received early physical copies of the game have been able to jump online.
Users on Reddit noted servers went live early this morning, though as of now it appears console players who are buying the game digitally will have to wait for its official release later tonight. Reports indicate that GameStop has sent many copies of the game out early, specifically the Power Armor edition, allowing those with physical copies of the game to hop on regardless of platform.
Source: IGN.com Some Fans Are Already Playing Fallout 76