As Bungie has announced on Twitter and on their official website, they're taking Destiny offline for maintenance for 4 hours tomorrow that is "if all goes according to plan". Destiny is going offline to prepare the game to some updates planned for the upcoming weeks the developer said.
"Once services are restored, your experience as a player will be unchanged".
"The updates we're making will be on our side, so you won't need to download or install a new batch of content".
The maintenance window will start tomorrow, on November 13 at 4:00pm GMT, and hopefully you'll be able to play from 8:00pm and onwards without any issues.