I've been getting 90k errors for the past two weeks as well.
My info:

Playstation 4
Mateus (via Aether)
Comcast (xfinity) and Centurylink (Qwest)
Washington State

My average download speed is 15 mbps, and I usually get about 13 mbps with Centurylink, and on Comcast, about 23 mbps download speed. I can log in and access the game from the launcher no problem. The first red flag happens when I open the Duty Finder menu and it doesn't load anything but the text "Obtaining Data." I usually have to close Duty Finder and re-open it a minute or two later.

I begin to experience chat lag and movement lag, but it is still possible to craft (after waiting for about 30-40 seconds per action). If it gets too bad, I get kicked off with a 90k error. I receive about 20-40 packages, but send nothing according to the network icon in game.

If I end up connecting to an instance through Duty Finder, I've got about three minutes before I get kicked with a 90k error.

Sometimes mine are also followed by 2002 errors, if I can even reconnect, which requires me completely closing and restarting the application.

The issues began a few days after Hunts launched.

Will this be fixed promptly? Is it even being looked into?

(Right before I DC'd in a dungeon today, someone else also complained about lag and getting dropped, so I know I'm not the only one, followed up by the replies on this thread.)