Okay so! What you've just seen is a mistake on my part but you should still have access to the full content on itch.io.
The newest content is the chapter you would have read to get to that point. Currently it is labelled Chapter Three but it essentially comprises what was originally written in the choicescript version of the game (chapters 1 through 4) hence the confusion regarding chapter titles.
(That, and in my files it is straight up labelled chapter four so rip)
Unless I've completely gone and fudged it, you should still have access to the new content plus a page I used to list out characters that I forgot to delete afterwards.
Hope this makes sense!