Hi, the function pulls back the current post types available. With your example, if you were to add another value to the array now, and visit the options page (not field the editor view) you should find that the new values don’t show up in the select… Or that’s at least what’s happening for me. This function only seems to run and get populated when you try and edit the repeater.
Welcome to the Advanced Custom Fields community forum.
Browse through ideas, snippets of code, questions and answers between fellow ACF users