On at least one alt (haven’t tried others) I disconnect when entering Gorgrond. This just started happening, and has happened 6 times in the last hour or so, across various attempts. Whether I cross into Gorgrond on a taxi from the Garrison, or from Warspear, or flying myself, the effect is the same.
When I log in afterwards, the game says I am in unrelated places, like Bastion of Twilight or South Seas, and I have to Help =>hearth or try teleport to graveyard. Hearth has worked a couple of times; other times I have to Alt-F4.
Other than Gorgrond, I seem to be able to travel normally around Zandalar and Kalimdor.
I renamed my Cache and WTF and Interface folders, but the effect persists.
I’m not sure whether it’s relevant, but after one of these, my Battlenet client showed a very short update to WoW.
There used to be a Repair option? should be in the Battlenet client somewhere, but I can’t find it, and a search doesn’t don’t find it in Support.
EDIT: See also this post World server is down, only on Gorgrond?!?! there may be a connection, since my alt was also on ER.
See also this post from over a month ago