As feared by @rahveein 2019 rclone appears to lock its config file while running.
Not a problem with static configs but syncing two OneDrive targets in parallel brings AUTH errors for the later started sync job*.
My workaround is using separated configs but I'm not sure this is intended behavior so I just tell you my sighting.
* each job runs flawlessly when it's the only rclone instance
Run the command 'rclone version' and share the full output of the command.
os/version: Microsoft Windows 10 Pro 21H1 (64 bit)
If there is an issue with the rclone.conf saving, we'd want to see it via a debug log so recreating it would be helpful as we've had numerous discussions on the rclone.conf / how it works and not saying you haven't found a bug, but if so, we'd need to fix it.