My level 60 Worgen Druid keeps getting Dc’ed while in flight form in Legion content, specifically in Haustvald in Stormheim with the Blizzard error message of wo51900319. I have reset the UI by going into the wow folder and renaming the cache, interface and wtf folders and deactivated my add on updater and it is still a problem.
Also I have been getting random DC’s across all characters saying that my subscription is expired, which of course it is not.
There are actually threads that have been created for your two issues:
I would add your information to those threads, which is preferred so all information is kept in one place. Any updates will be posted to those existing threads as well.