This looks wrong - our gateways should definitely support public IPv6. Seems like the only thing missing here is AAAA records. I’ll get those added to *.gateway.6pn.dev.
The IPv6-only system perhaps doesn’t implement DNS64/NAT64 or 464Xlat? It should. Case in point, ipv6test.google.com famously does not have AAAA records.
My server is hosted at a provider that allow to save some money by not having an IPv4 address and there is no NAT64, just plain ipv6 only. Everything works fine for my needs, it’s just a couple of services running.
@lillian Thank you, I’m able to now reach the gateway using ipv6.