Question about pinned topics settings

I’m dealing with a request from our moderators relating to how pinned topics work, and I found the following in our site settings:

What’s the difference between “automatically unpin topics” and “default topics automatically unpin”? I found some references to users being able to set a preference for pinned topics in their /my/preferences/interface page but that doesn’t seem to exist in my install.

I’m on version 9780f0fd52.

The user peference is only visible if automatically unpin topics is enabled.

Aha, thank you! So we’re not just setting the default, we’re removing the user’s ability to change it. That’s actually what my moderators were requesting.