Hi Chris, sorry that was 100% not the issue. Definitely something to do with having just levelled a 2nd character to 18. I and three friends all had the same issue, all resolved the same way. Some details to help you out:
- We levelled to 18 by getting to Theatre Settlement, doing 1st mission to rescue daughter, then had a friend in WT5 invite us to their session to complete the last two missions on story mode (bunker and Potomac) for mad XP. We then did the history museum and viewpoint in our own session. This unlocked L3 theatre and the DZ NPC, so we did the East and South DZ missions to gain access.
- We farmed the DZ a bit on the L18 chars and quit - not logging out, just quitting app or turning off the Xbox.
- Next login we noticed we can't see many BoO NPCs. Yesterday trying to do Union arena I could see and choose difficulty of mission and fast travel to it but not actually play, it just didn't start. Same for the missions I listed above
- The fix was the steps in my other comment in this thread, selecting the 2nd L18 char and logging out then logging into the main char.
Hope this helps, if you need more info I'm happy to help. Will try to reproduce the bug tonight by quitting from the L18 char.