Hi Michael Beckwith,
I did try to use pre_get_posts for admin view but not for posts per page, just to use “order by”. I did try commenting it out, and use different theme entirely, but its still not showing the correct result.
Other note is that in the custom post listing, if I click “Apply” in “Screen Options” it will show the pagination and update the number of items, but its incorrect. For example, i have 40 items and number of items per page is set to 20, so i should see 40 items and 2 pages in pagination section, but it shows 66 items and 4 pages. It happens to all custom post type.
https://i.stack.imgur.com/mCO8F.png
