https://wccftech.com/subnautica-below-zero-out-next-week/

Subnautica: Below Zero, the standalone expansion for the acclaimed single player survival game Subnautica, will launch on Steam Early Access, Epic Games Store and Discord Store on January 30th as announced yesterday by developer Unknown Worlds. Pricing will be $19.99.

Subnautica: Below Zero is also expected to land on consoles eventually. However, considering that the developers said the early access phase could take over a year (it did for the main game), Xbox One users could get it through Game Preview a lot earlier than PlayStation 4 gamers.