https://www.gamespot.com/articles/pubg-adds-squads-mode-on-the-new-savage-map-for-te/1100-6457915/

The new PUBG map, Savage, is currently available to testers--and only Solo is supported. But that is changing, as developer PUBG Corp. announced today in a Steam post that it is opening up support Squads on the game's experimental test server.

You need a key to access this, and if you were not able to secure one already you can grab one on the PUBG website here. There is not telling how long they'll be available for, so if you're interested, you should act quickly. There are "hundreds of thousands" of keys being made available, but given how big PUBG is, they could run out.