According to the Patreon release date post, the following:
"The breast expansion, ass expansion, and height potions are now fully functional for MC. I've also added some new characters, locations, and scenes."
Viewing post in The Expanding Alchemist 0.4 is now available! comments
https://www.patreon.com/posts/expanding-0-4-110657734
Public release on the 22nd. Just a couple weeks away.