How do you get around the upgrade page and keep mail classic on Yahoo Mail?

To bypass the upgrade page and keep Yahoo Mail Classic, you can try accessing Yahoo Mail directly through the Classic Mail link, which may still be available for some users. Alternatively, you can use a different browser or clear your browser's cache and cookies to see if that allows you to access the classic version. If these options don't work, consider using a third-party email client that supports your Yahoo account in its classic format. However, keep in mind that Yahoo may eventually phase out the classic version entirely.