That’s this friday, April 25th. The devs from Vostok Games confirm that the open beta should start pretty soon.
Survarium is basically STALKER the MMO. Please note: the current beta version of the game includes the team-based competitive multiplayer mode only. Anyway, more on everything Survarium related, including the beta sign ups, is available on the official site. Here’s a video on what currently is going on inside Vostok Games and how the developers get ready for the Survarium Doors Open Day event.