Microsoft Flight is scheduled to be grounded on October 14, 2014 when the multiplayer servers will be shutdown. This will affect online features, such as multiplayer and aerocaches; the single-player experience should remain largely intact.
Questions regarding this announcement were addressed with a short FAQ list:
Can I join Flight if I am a new player?
No. Product keys are no longer being issued to new players.
Will I still be able to fly single player?
Yes! You will still be able to log in to your Games for Windows Live account and play.
Will I still be able to use DLC (i.e. Hawaiian Adventure or Maul M-7-260C)?
All previously purchased DLC will continue to work and will be available to re-download via the Games for Windows Live Marketplace.
Will I still be able to earn achievements?
While some achievements will no longer be obtainable, you should still be able to obtain any of the achievements related to offline play.
Read the full Microsoft Flight! Announcement Here.