https://www.gamespot.com/articles/fallout-76-beta-heres-when-it-starts-on-pc-ps4-and/1100-6462097/

We've just gotten a flood of new information on the upcoming Fallout 76, and you can read all about it in our hands-on impressions. If you're eager to try it for yourself, the Fallout 76 beta kicks off quite soon. As we previously heard, it'll come to Xbox One before other platforms; it begins for Xbox One on October 23 and on October 30 for PlayStation 4 and PC.

In an FAQ for the beta, Bethesda stressed that its purpose is to "stress test and break the game," which means that servers will be "online during targeted timeframes so we can get as many people as possible playing at the same time." Although specific times have not yet been confirmed, the company said the play sessions could last anywhere between four and eight hours. Overall, the beta will go on until a few days before launch.