We are aware that some players are seeing the Sail 630 Nuclear Bug message and then are unable to connect while seeing a ban message. The ban message is not a product of disconnect errors. For questions about enforcement policies, please visit this link.
I've spoken with our teams regarding the recent Sail 630 Nuclear Bug threads and reports, and here's what I have to share.
Sail 630 Nuclear Bug: This error string is currently presented instead of the standard disconnect language when a disconnect occurs in the Zombies menus on PC. PC players would typically see, "Connection to the Blizzard game server has been lost. Please exit and try again. BLZBNTBGS000003F8."
We encourage players to continue playing Zombies as per usual, which includes chasing high-rounds and personal bests.