Actually BJZ notes have been confirmed as inserts.
According to CPMS Newsletter Volume 13, Number 1 of March 2005, under Insert-Replacement Note Update, they listed $100 inserts as follows:-
Range (Mil)
BJZ 5,049 - 5,058
BJZ 5,364 - 5,372
BJZ 5,427 - 5,436
BKE 2,511 - 2,520
Among other inserts of interest listed are:-
HNN 0,020 - 0,060
FEN 2,502 - 2,556
BER 9,684 - 9,693
BER 9,702 - 9,711
AZA 0,000 - 0,009