it might be possible that this isn't released on xbox yet. i have done some searching to try and find an exact timetable of when the three episodes will be released, but haven't found anything yet.
so, as it stands, i purchased the season pass and while episode 1 is listed in the series, there is no play button. i can watch the teaser video but that's it. i've refreshed my purchase history multiple times, but no luck.