The holidays are right around the corner and to take advantage of the holiday traffic increases we see in Microsoft Store, you’ll want to update or submit your app or game no later than Monday, November 13th for Thanksgiving (US) and Thursday, December 13th for the Christmas holiday. You can see the full list of submission deadlines below.
Updating or submitting your app or game early ensures that they will be available during the holiday season!
Source: Windows Blog
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