Changing Page Authors in 2.8

I appear to have stumbled onto a bug…will see if I can describe below.

Let’s say I have two admin users (both with full administrator capabilities) on a blog, ‘admin1’ and ‘admin2’. I log in as ‘admin1’ and change the author of a particular page to ‘admin2’. I log out. I then log in as ‘admin2’ and go to the Edit Pages panel of the dashboard.

Here is the problem: when I click EITHER the ‘Edit’ or ‘Quick Edit’ links underneath the name of the page and try to change the author back to ‘admin1’, ‘admin1’ DOES NOT SHOW UP in the drop-down list.

Hopefully this can be fixed, as I am not sure how to change a page back to the original author in this scenario.