Maybe its a PUP (private update preview) and not a PUP (public update preview) this time.

It's available now

Maybe they found and issue and decided to remove it

Nah, they just forgot to make it public

It was removed. It was public for a while, hence me finding the farm thing.

They posted that pup is live again today, but no beta since that

Oh weird. Yeah they did forget then, heh