To be clearer: this AAAA record is for the same subdomain than an A record which is being updated by dyndns. But because IPv6 addresses don’t change, I never need to update the AAAA record.
I was wondering: if there is an update to a subdomain’s IPv4 address (and nothing sent for the IPv6 address), does deSEC delete the IPv6 (AAAA) record of that subdomain?