So. The day before yesterday I was going to do Grim Batol mythic with a couple of friends and note that we did Grim Batol the day before that but when I entered the dungeon I instantly got disconnected with the errorcode WOW51900323 and it then kept disconnecting me everytime I tried to log in on the character I was playing so I tried another character and the same thing happened. I eventually got the characters moved so I can play on them but now I got a experiment character that I keep trying to enter Grim Batol with but the problem is still there and I get disconnected with the same errorcode. It only happens in Grim Batol all other dungeons in the rotation works just fine.
I have bug reported this but it would really suck if I cant do Grim Batol when m+ starts tomorrow because there are alot of nice things in there for both my characters.
Would be nice to atleast get some form of response from Blizzard that they are looking into it.