Can no longer access email more than 11 months old

Did AT&T delete all the old emails?

I used to be able to search back years and years for email on my legacy sbcglobal.net account using webmail. Now, out of the blue, I can go back no further than July 25, 2021 (I am searching on June 28, 2022). When did AT&T decide to prevent us from accessing old email? Did they delete it all? Where did it go?