I talked to Iccreations a few months back. He didn't abandon it because he was busy with FILF. He abandoned it because of the update to Patreon's terms and services which declared no depictions of Incest (This actually hurt a lot of game developers). He didn't think it would work to try to retcon the game so all the characters were unrelated, so he abandoned it instead.
I asked if he would be willing to let someone inherit and finish the game, but he told me that he wanted to keep the characters because he likes to use them for easter eggs in his new games (which true to his word, he has been doing). I know, I'm pretty bummed about it too, but honestly, he was excited to work on this project and he was a victim of circumstance, so don't blame him.
I will definitely miss the characters, but FILF is still a great game (I personally don't care for altered destiny, but I know a lot of people like that as well.