I believe you sir are correct. I could be wrong but I do think your logic on this one is correct. Itch.io has a terrible system that treat sales separated from regular purchases. It will also give you special download links for things that got sold in bundles or special sales.
So it confuses it self when you try to download something from the items page instead the download link and will at time be like you don't own this item do you wish to pay?
So unless you really want to play it right now I would wait for the early access to be over and then decide from there.