There are multiple locations for Source Control settings that do not correctly reflect each others state.
In editor preferences, Auto undo operations does not reflect my current setting in Revision Control Login. Toggling either setting with both windows open updates this and puts it back in sync.
Also under Editor Preferences>General>Loading & Saving, Auto checkout toggles the wrong setting in the Revision Control Login window and just generally behaves oddly as shown in this video.
I would expect all settings related to Unreal Source Control be located within the Revision Control Login window anyway, and nowhere else, Editor Preferences in UEFN is already unwieldy and it is nowhere near the wall of settings UE has yet, anything to trim it down and keep things in appropriate, expected places.