BTB is broken and devs give no info about that but to enjoy holidays.

Try going into your fireteam options and changing the privacy to open. It still doesn't work 100% of the time but its gotten me into some games.

BTB is the only game mode I enjoy on multiplayer, however queuing for it is a nightmare. Constant “disconnected from server”, “request timed out” or whatever else. Sometimes I’ll even get the join and instant error loop so I have to restart my game. Why can’t this fix this or just put a Dedicated BTB slayer list that works?

Why is it so hard to join Big team battle?