The subject (almost) says it all
I've got an RB5009 attached to a business Comcast line with a /28 IPv6 static block and (supposedly) static IPv6 prefix.
That's the problem -- the last part -- the prefix is "almost" static (which doesn't count....) I get 260311bd:11xx::/56, but it appears I can only count on the /60. However, that /60 keeps changing every so often. Sometimes it's 11bd::11c0, other times 11d1 etc.
Comcast is supposed to be static if my DUID is static right? I tried checking use interface DUID but that doesn't seem to matter and I can't find documentation on it anyway.

So....

• What is the correct way to do this (if it can be done at all)?[/list
  • What does "use interface DUID really do?
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