Went digging through the wayback machine to find it and its available here: https://web.archive.org/web/20230117024804/https://www.ahist...

which leads to: https://drive.google.com/file/d/16ATMkf7SAwwjePZZZb0mFrFX5rM...

Festivals quite often want films to be "exclusive", so maybe it's to do with that.

Yes, but at least “From summer 2023 onwards, it will be permanently downloadable from this site.”

RemindMe! 3 months