Post Export isn’t including some (or any) posts!?

For a bit of background, I’m creating a new version of an existing WordPress website (my new one is local), so I want to export posts from the live site (which are spread into categories), and import them into the new site.

The client has requested to keep / import only posts from the start of May 2024, to try and purge some old content.

When I look at the current site, for one category, it’s showing 11 post count. However when I go through the built-in exporter, and filter by Posts -> Category (the chosen category) -> From Date (May 2024), the export file doesn’t contain any posts, but instead shows lots of author records (even though these authors or ‘users’ are not even listed in the export options.

I have no idea what’s happening, could anyone help identify why this isn’t working as expected?