But It seems like they're actual/genuine Mixdowns being exported. Most of the recent leaks were multitracks featuring full ProTools sessions, so all you'd need is the original program (and plugins dd), and you'd be able to bounce different demos/edits as the producers left them. There's extra stuff going around as well, like the "Just Dance Ruff" and an alt. Poker Face acappella featuring a different vocal take (that someone pasted over the official instrumental); these were not part of the multitracks but real files.
The way they've uploaded the alt. Fashion Of His Love acapella with "you don't need that jacket, or that string of pearls" that someone used to create that "Acid Washed Girls" leak, but we're yet to hear the "I am fashion, music, groove, baby I was made to move" part/demo (?)... hell!