itch.io

This serves as another reminder that, when you have a world wide audience, you should publish the release date and time in UTC.

Or, at the very least, you should add an extra day and leave people who are in the earlier times zones happily surprised.

It looks like a new version of the demo was published along with the new chapter update.  If you're using the Itch.io client, you probably chose the wrong update to install.  

You should uninstall and re-download the full 'Chapters 1-4' version.