Bungie has announced scheduled maintenance for Destiny that will start at 8 AM PDT and end at 12 PM PDT. During this time, servers will be down and players will be unable to log in. You’ll receive a notification for when maintenance will occur shortly before it happens so plan your raids and Prison of Elders runs accordingly. It should be noted that the corresponding companion app could also go down in the meantime.
This isn’t the first maintenance period that Bungie has had in the past month or so. It’s been working on servers to prepare the game for its biggest expansion yet with The Taken King which launches on September 15th and adds a ton of new features to the game.
Nonetheless, if Bungie does change something else, it will likely let you know after maintenance is over. Stay tuned for more information on the same and read up on The Taken King and its changes in the meantime.