Does this update oxide when it sees that an update is neeeded, or just tell you that you need to update? And, if so, can that just be done during the scheduled restarts (daily)  and not just imediatly after it sees an update has dropped?

All this does is shut down your server.

I'm sorry, but whats the point of that? I already get the email notification for the update and the console notification that its out of date, and the server can usually still run without running an oxide update right away. It would be awsome if it could run the update, but in sure thats impossible for the various hosting options that people are running.
Love the smooth restart process for daily wipes, Its so much better than the scheduled tasks I can set up with my host.

It isn't possible for a plugin to run when the server is offline, so it can't update anything. All it does is check for updates and restart so your external tools can update.