I think this has to do with DHCP: you are using static IP (dhcp=0). Right after firmware upgrade, the controller is back to DHCP mode. During the import process, the IP address will immediately change after the DHCP is set to 0, and therefore the import cannot continue and complete. We highly recommend keeping DHCP but use your router’s DHCP reservation to create a fixed IP. This way there will be no issue with import, and you are less likely to get into IP conflict issues.
In any case, if you restart and try ‘import configuration’ again it should be able to complete the import.