This change introduced a check to only allow ip-version both if server is set to members.dyndns.org: https://vyos.dev/rVYOSONEX604a12d65ddc5ca81bc1a8a7bbdcb7cf40a7897d
I'd like to use the PowerDNS-Admin API which implements dyndns2.
This implementation also supports both ip versions: https://github.com/PowerDNS-Admin/PowerDNS-Admin/blob/master/docs/wiki/features/DynDNS2.md?plain=1#L13
I reverted the commit and ddclient successfully configured both A and AAAA using the PowerDNS-Admin API.