I dont know anything about animators and how they work but if its like some of the other works that I have tried out (editting videos, etc.), then for example, in this week, they will plan to release a new episode on the day that it is supposed to come out and during the week, they will work on and animate a future episode for maybe next week (if they can do it quickly) or some unknown week in the future (if they cant finish an episode right before the upload week)