2002::/16 [6to4] & abuse

[dhubbard at dino.hostasaurus.com (David Hubbard)]

Curious if anyone can tell me, or point me to a link, on how 2002::/16
is actually implemented for 6to4?  Strictly for curiosity.

We had a customer ask about blocking spam from their wordpress blog that
we host and the spammer was using 2002:af2c:785::af2c:785, which was the
first time I'd seen wordpress spam coming from IPv6.  Per RFC3964, I'm
guessing the 175.44.120.5 is just a relay router, not surprisingly, on
the China Net network and the spammer was native v6?

I see that net advertised from 6939 (HE) and 1103 (SURFnet Netherlands)
from the perspective of my feeds, so that just got me more confused.

Thanks,

David