This is in the patch notes:
System Mail Deletion & Organization Changes
-Beginning with this update, System Mails will now remain in your inbox for a limited time, after which they will be deleted. This mirrors the current behavior of player-sent mail.
System Mails include:
-Mails sent by NPCs (such as Hirelings)
-Mails containing Collector's Edition rewards
-Mails sent for completing PvP activities (such as Rewards for the Worthy and Battleground completion rewards)
-Mails sent for completing random dungeon runs, such as Premium Undaunted Exploration Supplies mails
-Mails containing Guild Trader purchases
-Mails that have been 'bounced' from another player (such as CoD items that have been refused)
-When this update launches, all System Mails you currently have in your inbox will be given a timer of 30 days. When that timer gets close to running out, the mail will be highlighted with red text and iconography to indicate it will soon expire. When a System Mail's timer expires, that mail (and any items or gold that might be attached to it) will be deleted.
-In addition, for Keyboard/Mouse mode only, we've added headers to separate player-sent mails from System Mails.
Now I know some of you use your mails as banks, so be ready for this as your attachments will be deleted.
However, for me I was saving mail from when the game first started, Some of y mail from ZOS dates back 84 months at this point. So if you (like me) are nostalgic for these early emails and kept them. Start taking screenshots now.
Edited by BlueRaven on February 24, 2021 12:31AM