The 2300 UTC fax transmission from JSC on 16971.0 USB incorporates a block labelled "NX." This contains the latest maritime navigational warnings, in Japanese. It is repeated, by itself, at 0200. You can see how band conditions have usually deteriorated by this time.
The closing of a large utility radio transmitting site once operated near Tokyo by the Japanese telephone company has caused several services to scramble for new facilities. The fishery station in Kagoshima Prefecture, in the south of Japan, now has several of these, including at least this one Kyodo frequency and the Tokyo VOLMET. It's well situated for good coverage of the Pacific.
All fax signals are tuned 1.9 kHz lower than their listed frequencies.