According to the dev's blog, in his post from August this year [link], he estimates the release to be possibly late 2017. I guess you will have to be patient. He shared some more infos about the game progress in his newer posts.
I'm pretty sure that Quells said that the remake (Phoenotopia: Awakening, I think?) would be before the sequel, because otherwise there would be a regression in the quality of the game. The original post is here... (Can anyone teach me how to put a clickable link?)
http://phoenotopia.com/post/149235269068/announcing-phoenotopia-remake
PHOENOTOPIA AWAKENING GOT ANNOUNCED FOR AUGUST 20, 2020! I'm so excited holy, the game looks beautiful. Trailer here: https://www.youtube.com/watch?v=I7qY3fntoLg
