Score! Found this today, can’t wait to try it out. This describes a much cleaner solution to my AT&T IPv6 issues.
The NVG589 modem automatically connects to the AT&T 6rd tunnel gateway to provide “native” IP6 for customers when IP6 is enabled. Each static public IP provides the AT&T customer with a /60 subnet via the 6rd protocol. The tunnel has near native performance… #ATTCOMMUNITY
Source: AT&T Support Community