Whilst further map data can be added to a device which was setup before map servers were turned off in June 2018, as far as I can see there is no way to re-commission a device after reset or re-flashing firmware since always required a few mb's of map data to be downloaded to initiate.

As a postscript I have seen posted that flashing eMMC image with map data will enable it to establish location, but have not had occasion to re-flash a device for a good while to prove/disprove this.