You are able to undo project setting check outs when you are on a different machine. As a BIM 360 Team admin, you can force undo check outs.
To undo a check out on a different machine
The Project setup dialog displays. If this is a collaboration project and the Project Settings have been checked out, an informational note at the bottom of the dialog box shows who has the settings checked out. Hover over "on another machine" to display more information about the check out.
To force an undo check out
The Project setup dialog displays. If this is a collaboration project and the Project Settings have been checked out by someone else, an informational note at the bottom of the dialog box shows who has the settings checked out.
An informational dialog box is displayed, showing the username of the person who has the drawing checked out.