What happens if I import a device that’s already in Fleet?
If you use Fleet’s Import function to import a device that’s already in Fleet, then don’t worry — you won’t break anything. However, the information in the imported CSV will overwrite information in Fleet.
If you have a device in Fleet with the serial number 1015, and use a CSV file to import a device with the serial number 1015, the CSV fields will overwrite whatever is present in Fleet. For example, if the serial number 1015 device in Fleet had the assigned user firstname.lastname@example.org, but the serial number 1015 device in the imported CSV file had the assigned user email@example.com, then Fleet would change the assigned user to firstname.lastname@example.org