I have all 4 DLC installed, however this is the first time I've done BoS missions, so I don't know if this was present in earlier versions of the game.

Get quest, progress quest to the point that I have the missing pistol - I can enter and leave the bunker without issue. As soon as I turn in the laser pistol and complete the quest, I game locks up as soon as I try to leave (loading screen flashes up, then goes black. Have to hard restart XB to resolve).

Replicated numerous times last night and today, so not a one-off. Just confirmed within the last few minutes and quest completion seems to be the source of trigger for the issue.