The note concluded AT&T delegates a single /64 and that reading the
address pattern as a /60 was a mistake. A later finding in the same
session overturned that by reading the BGW's own statistics page, and
that correction was never written down; it survived only in the
transcript and surfaced again while assessing whether more prefixes
could be claimed.
The gateway holds the /60 and rations it, keeping half for itself and
delegating the top eight /64s one at a time. Both observations agree:
a prefix-id only carves within a delegation already held, so the
earlier test could not have moved a lone /64 regardless. The limit is
that UniFi solicits once, which makes the requester the ceiling rather
than the carrier.
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