DNS Queries for subdomain of local domain are not forwarded upstream

[bchmnn]

I have the following problem:

• I have setup AGH as DHCP and DNS server on my local network on a machine with a static IP, e.g. 192.168.0.100.
• Say, I have the domain "bar.foo" setup as local_domain_name in AGH's DHCP config.
• I also have some DNS rewrites:
  • bar.foo -> 192.168.0.100
  • baz.bar.foo -> 192.168.0.100
  • *.bar.foo -> A
  • *.bar.foo -> AAAA
• On my favourite registrar, I have entered an AAAA record for hey.bar.foo to some IPv6 address of a machine outside my local network.

Now, when I run dig AAAA hey.bar.foo within my local network, I expect AGH to forward the query upstream to my favourite registrar. But instead it answers with SOA fake-for-negative-caching.adguard.com..

What have I configured incorrectly, or what have I misunderstood?

Edit:
I've also tried adding [/hey.bar.foo/]8.8.8.8 as upstream dns server. Unfortunately, this didn't help.