Search - "This URL uses V3 format and will be deleted. This will be recrawled using V4 format"

Hello,

We are getting the message "This URL uses V3 format and will be deleted. This will be recrawled using V4 format" in a SharePoint 2019 search service application in a incremental crawl.

New items are only crawled in a full crawl. I already tried the "Reindex library" option, same results.

This is a Publishing site in host named site collection in a SharePoint 2019 farm that was configured using the approach in https://blogit.create.pt/miguelisidoro/2021/08/11/how-to-configure-https-with-http-redirect-in-sharepoint-2019-using-host-named-site-collections/.

The address uses to access the site are HTTPS but the start address in the Search Content Source is HTTP (look at the my blog post - link in the post).

The crawl log only shows this message: "This URL uses V3 format and will be deleted. This will be recrawled using V4 format", nothing else.

Any clues?

Thanks

Miguel