I have been playing for months on Behemoth, and never had any lag issues. This past week, no matter what time of the day or night, I will run fine for the first five minutes, then the music starts skipping, npc's disappear, invisible mobs hitting me, and I have no choice but to log out. I also play ESO, and am having no lag issues there, and I also have all settings at minimum to improve performance.
Not sure if anyone else is experiencing this, but just wanted to bring this up because for me it is almost unplayable currently.