Closer inspection indicates it wasn't multiple logins, rather the same login window re-opening itself mulitple times when the close button was clicked; full spectrum of Win Def scans came up with nothing.
Win11 22h2 update seems to have corrected the issue but now there's different problem with apps/documents returning "The specified user does not have a valid profile." warning when I try to open them. Beginning to wonder where this rabbit is going to run next.
Addendum:
Seems like second restart after 22h2 update has cleared everything up; thank you for your time and patience.