I don't think we're getting anything from the developer any time soon. If you want more content and have some spare cash, there's a good amount of endings out for Day 4 already on their Patreon for $1.50. I think it's a good deal, I spent about 2 hours playing them all. The artwork and horror is even better. There's even some animations and each ending has unique features. I think Day 4 is the final day, based on what the developer said and how the endings are like, so I recommend them if you want conclusions.