Reimage Sophos Firewall not possible

Hello, Yesterday I tried to reimage a Sophos Firewall of ours but I didn't succeed. I followed the instructions as provided on https://docs.sophos.com/nsg/sophos-firewall/21.0/help/en-us/webhelp/onlinehelp...
Possible to Backup/Restore to a different (higher/lower) model?

Hi, i was just wondering if it's possible with the latest SFOS to backup and restore from a XG 210 to a XGS 2300 and from a XG 230 to a XGS 2100? Thnaks alot!