Yup! FNaS 4 Halloween Edition is going to get a huge overhaul update at some point within the foreseeable future! This overhaul will include but is not limited to:
Overhauled AIs to be more chaotic and more difficult (the original game was too easy)
The replacement of the "challenges" in the extras menu in favor of an all-new "Lunatic Mode", which makes all of the characters faster and adds new mechanics to all of them!
2 entirely brand new characters, bringing the roster to 10 total
Completely redone graphics with the lead artist being @ColdSky0
... and probably more!
I'm really excited to share this news with everyone, mostly because as proud as I am of the original version of the game, I felt like a lot of the potential of the game wasn't quite hit, and I want it to be the best it can be. No confirmed release date.