They've already said they're working on something else (possibly in-game mail system)
[quote] downtime for the game[/quote]
Scheduled downtime is always listed here:
https://help.bungie.net/hc/en-us/articles/360049199271-Destiny-Server-and-Update-Status
English
-
Don't have much faith in this considering that a lot of people don't even get emails if they are subscribed to the Bungie mailing list. Maybe that changes though!