It is not a MMORPG, it is a game that needs to be finished. Devs are not bound to add "content" every 2 months, let only every 6 months. They are supposed to finish the game in a reasonable time laps, and if this means in 2 years, that well might mean in 2 years without intermediate update.

Now, that's on your playstyle. Either you go play another game until next content update, or you keep on having fun exploring, exploiting, building, fighting... For you do have fun in those doings, don't you?