Latest annoying thing about AT&T’s residential IPv6 implementation: because you request multiple /64 prefix delegations, each with an SLA ID of 0 (instead of one /60 or /56 for example), there’s no way to ensure you can allocate the same delegation to the same interface. You don’t know which /64 you’ll get for each PD. Also, they will occasionally get all jumbled up, such that 0x0f and 0x0d get swip-swapped.

Comcast handles IPv6 much better, doing things much more by the book. Boo, AT&T. Boo!