Auto-Enable Not Working

Running Version 2.6.0 on WP 5.8.1. The Auto-Enable setting in the Post Types tab doesn’t seem to work as expected. My settings:
– Active: Active
– How to expire: Draft
– Auto-enable: Enabled
– Default Date/Time Duration: Inherit from General Settings (+6 month)

When I create a new post with these settings, the Enable Post Expiration box is prechecked and the datepicker correctly shows the date 6 months out. But when I publish the post and view all posts, the Expires column reads: Never.

If I Quick Edit the post, the Enable Post Expiration box is unchecked. If I Edit the post, the box is still checked and shows the correct date, 6 months out. If I come back the next day and Edit the post, it shows a new date, 6 months from the new day, so this is not getting set or saved.

I can work around it by manually unchecking and rechecking the box in the post or by just disabling the feature and force users to always have to check it to enable, but we prefer the auto-enable feature.