would be a good idea to test the backups on 7, and double check the release notes, they hold just about every caveats. The 7to8 upgrade was not horrible, if you have backups, you could always attempt the upgrade after taking backups, then if successful take new backups, test, then install new drives and restore. depends on how paranoid you feel.

If this was a production system, that is probably the change plan i would follow, but in production I would also be able to migrate VMs. I am not nearly as careful in the home environment.

what about that doesn’t work? just because you don’t know how doesn’t mean not possible.

https://developers.cloudflare.com/dns/manage-dns-records/how-to/managing-dynamic-ip-addresses/

https://github.com/ddclient/ddclient#using-ddclient-with-dhcpcd

https://openvpn.net/community-resources/configuring-openvpn-to-run-automatically-on-system-startup/

maybe a vpn provider that uses openvpn? advanced setup but you can have an openvpn client auto connect on boot and bind the mail and ddclient to the tunnel interface.

cloudflare has good support for ddclient, so when your IP changes updates are automatic.