Originally posted by Nefrarya:

Mistlands is currently slated to come out on the experimental Public Test Branch (PTB) sometime this year. It's a great opportunity to start a new world, just mess around in it, and help the devs find bugs or improve game balance.

Release on the main branch depends on how much bug fixing & balancing needs to be done. In the worst case this can apparently reach into early 2023, if I understood correctly.