tl;dr: Tesla renamed the purchase contract in their online customer portal from saying "Full Self Driving" in the title to saying "Full Self Driving (Supervised)" - but at the same time removed the ability to redownload the contract.
Hopefully owners saved their original contract copies that call it "Full Self Driving".
When we got our Tesla with FSD back in 2017-2018, the website had all kinds of wild claims about FSD being ready and only subject to regulatory approval, too. As well as capabilities. I feel you'd have to download/screencap everything to get a sense of what they were advertising, promising, and implying.
Changing contract language like this is insane. Amending FSD to "Supervised" is absolutely a material change.