That day was back in 2013.

* http://jdebp.uk./Softwares/djbwares/

Felix von Leitner added support in a different way some years even earlier than that, requiring new record types. The 2013 mechanism simply extended the existing + record type (and indeed all of the other record types that have an "ip" field) so that one could give it IPv4 addresses or IPv6 addresses.

* http://jdebp.uk./Softwares/djbwares/guide/commands/tinydns-d...

sadly, djbdns will probably support AAAA records long before the majority of the Internet.