Same thing here - Bleeding Hollow. "You have been disconnected from the server. (WOW51900319) - https://us.battle.net/support/en/article/21758.
WOW version: 11.0.2 (56819) (Release arm64)
Battle.net version: 2.36.0.15021
Battle.net Update Agent Version: 2.35.5.8868
macOS version: 15.0.1 (24A348)
Apple Mac mini M1, 16 GB RAM
I also noticed that when I come back in, my a) keyboard is set for a specific user, and b) my talents are a different saved build. Not sure if that helps.
Noticed the same issue after updating to 15.0.1. I was getting consistent disconnects every 10 minutes or so. I also thought this was a WoW issue at first, but it indeed could be partially a macOS issue. It seems there was a set of issues with the network stack on 15.0.0, and while fixing them in 15.0.1, they introduced a different set of problems.
I’m not sure what the exact cause is, but it has something to do with the way firewalls are working. If you happen to run a third-party network filter like Little Snitch, this could be the case. There is a blog post on its developer site (obdev.at → blog) about this issue, with a possible fix coming in macOS 15.1.
While I can’t advise disabling neither the built-in firewall nor third-party network filters for obvious reasons, turning off only the built-in one while still keeping Little Snitch enabled helped me with the WoW disconnects.
Nopp, great info. Thanks, and I was just reading about this when I found your reply.
For others in this thread, are you on macOS 15.0.1?
Just started noticing this at the same time, just after upgrading to macOS 15.0.1 as well. Just turned off the macOS Firewall in System Settings, will take note of the result and report back whether it seems to have helped or not.
After being on and doing delves etc. for over an hour, I did not get the “You have been disconnected” message even one time. I think this might be a workaround, until either Apple or Blizzard figure out what broke.
Yes, I have not experienced a disconnect since turning off the macOS firewall.
I have massive disconnect problems since 15.0.1 upgrade, too. Eight disconnects during one hour of play. I haven’t tested turning off the MacOS firewall yet, though.
Thanks, I was wondering if it was the new Mac update that had something to do with this issue.
Turning off the firewall has worked for me. An unfortunate workaround.
having same issue - can we report bug for fix?
Having run WoW the last two days with deactivated firewall I can confirm that in my case everything works again and the 15.0.1 macOS update is the culprit.
Re-activating the firewall and logging into WoW leads again to constant disconnects.
Would anyone by chance be running Little Snitch? I noticed that the last update re-enabled the macos firewall so I had two firewalls running, which is very undesirable.
Endlessly… 
Nopp, fyi - on 15.1 with the firewall enabled and no disconnects yet.
Getting constant disconnects regardless of what network I am on. This is really making the game unplayable.
always skip the next major version of the OS for awhile 
it takes some time to work out the kinks.