Is anyone seeing sporadic issues reaching security.ubuntu.com over #IPv6 or have contacts at #Ubuntu / #Canonical?

[nygren@hachyderm.io]

Is anyone seeing sporadic issues reaching security.ubuntu.com over #IPv6 or have contacts at #Ubuntu / #Canonical? I'm seeing failures against some of the IPs they hand out but not others and also only from some places in the world. eg, 2a06:bc80:0:1000::16 seems to be returning errors from about half the places I've tried. I've not yet seen this issue in IPv4.