The game wont be finished for quite some time I believe.
Based on what we have seen and how much we know, there will be at least 2-3 more episodes, IF the developer rushes the story. Otherswise probably more like 5 I think. (speculations)
I don't think the game will be done in near future, since his storytelling is very good. Therfore "rushing the story" is not expected.
If you dislike waiting for new episodes, I would recommend you to not play it yet. I will probably take some more years to finish the game. But I also recommend saving this page or game, so you won't miss out in future. This game is one of my favourites and I would recommend playing it 10/10 times.