https://www.pcgamer.com/the-next-fallout-76-beta-for-xbox-one-happens-this-saturday/

The first Fallout 76 beta for Xbox One took place yesterday, giving those who pre-ordered a nice four-hour window to wet their whistles. The timing wasn't convenient for everyone: the beta began pretty late in Europe and pretty early for those on the US west coast who work during regular business hours, so not everyone got a chance to play. The next beta period has been announced by Bethesda, and unfortunately it's not until this Saturday. Double-unfortunately: it's only two hours long this time, instead of four.

The Xbox One Fallout beta will begin on Saturday, October 27, at 5 pm Eastern, and end at 7 pm.