https://www.polygon.com/2018/10/10/17960246/fallout-76-stress-test-beta-xbox-one-live-gold-insiders

Some Fallout fans will be able to get their hands on Fallout 76 later this week, thanks to a “stress test” of the game that will kick off before Bethesda’s official beta. Unlike the Fallout 76 beta (branded as the B.E.T.A.), which will be open to those who pre-order the multiplayer game, the stress test will be much more limited.

In order to participate in the Fallout 76 stress test, Xbox One owners will need to have pre-ordered the game, be an Xbox Live Gold subscriber and be an Xbox Insider member. Meeting those qualifications does not guarantee a spot in the stress test, however. Bethesda will offer the stress test to select qualifying players — and only in North America.