Version 2020.10.06.2128
From the Web Admin. Going to Search -> New Shows/Seasons. Clicking on a TV show, and choosing + New Series Pass. For Padding, I can choose any padding option except None in both the before and after drop downs.
In Settings, my default padding is 1 min before and 1 min after. If I change the default to None and create the Series Pass, I can then choose None for Padding for a specific TV show.
If in Setting if I change the default Padding to 3 mins before and 3 mins after, following the same steps, it defaults to 3 mins before and none min after. If I refresh the browser (from the Setting screen) and begin again, I get 3 mins before and 3 mins after by default, but unable to over ride Padding to None.
From the DVR/Passes screen, choosing a Pass the Padding options work as expected.