Interesting. Anyone know what they mean by
We are using a 'swamp' class C 192.94.73...?
Edit: Found https://tools.ietf.org/html/rfc4632 (CIDR: The Internet Address Assignment and Aggregation Plan), which says this. Still not quite sure what they mean.
Note that, as defined, this plan neither requires nor assumes the
re-assignment of those parts of the legacy "Class C" space that are
not amenable to aggregation (sometimes called "the swamp").