Google DNS64 misconfigured?

I had an ipv6-only lab environment cease being able to browse much of the internet on Monday. Tracked the issue down to google's public DNS64 service; the following queries should return DNS64 responses from the 64:9bff::/96 prefix, however, I'm getting 0 DNS64 answers from dig on both their servers for the last 60 hours:

dig @2001:4860:4860::64 AAAA
dig @2001:4860:4860::6464 AAAA

DNS works fine, just not DNS64. A forum topic [0] suggests this behavior might be intermittent but no official response from google there. Is google's public DNS64 down for anyone else?


I have seen intermittent issues with IPv6 queries to google's
nameservers as well. Some sites simply would not load, which is what
caused me to notice it.


I do not regularly use their public DNS64, but those queries also return no ANSWER for me from a couple of test points when I just checked now. One is on Teksavvy (AS20375) crossing through Peer1 (AS13768), the other crosses directly through peering with Google at the SIX.