Been upgrading 3 x ASG220 now with ASI USB stick.
The system does not auto reboot after finished installation which is ok, but if you use the menu buttons on the hardware device to reboot nothing happens except the text "Rebooting now" but it will hang like that forever.
Only power off/on on the back of the appliance works.
Can't test with never versions since only version 8.270 can be downloaded for ASI.