I looked at
RIC VII #91
Antioch, and it did not list that
officina. Fifth being reserved for the three Caesars in bronze for the first issue. The ninth offina issued the second issue of this series (#113). Ten
officina were employed at this time according to
LRB.
RIC has holes in it and must be updated...have you ever visted the website
NOT IN RIC? Very informative and fun to surf and do research.