In the coming weeks, we will be updating the code that powers our login system. When we make this change, all Archive users will be logged out of their accounts.
To avoid permanently losing access to your account, make sure you know your AO3 password and can access the email address associated with your account. If you forget your password and your email address is not up to date, you will not be able to request a password reset! (Edit, December 25: If you're sure you know your password and you regularly receive emails from us, you don't have to do a thing.)
Please take a few moments and follow these steps to check or update your account's email.
We will not deploy these changes until after December 13 to give users time to update their information. Additionally, we will give at least 48 hours notice on the AO3_Status Twitter account and our Tumblr, as well as on the Archive itself.
If you find yourself logged out and need help accessing your account, please do not leave your email address in public comments! Instead, you can contact Support about technical issues (e.g. password resets not arriving), or get in touch with the Policy and Abuse team, who can assist you in verifying that an account belongs to you.