Logged in to check my Overseer stuff, and got the message that I had new mail. When I opened my mailbox, the chronoportal event announcement letter was there, but it was greyed out as if it had been read, AND it thought it was 29 days old...
Think someone might be reading your mail then - perhaps @Dreamweaver, during yesterday's Time Warp? Couldn't reproduce on Myst's account, all 5 characters had the regular mail.