A Better Lorica is a sidequest and instructional quest which explains the working of the Crafting system in Expeditions: Rome. This quest can be started after adding the Armoury to the Legion Outpost. After talking to Sextus, he suggests that Julia Calida lorica worked quite well to disguise her as a man, but now that her true identity is known, it should be adjusted.
Dismantle the old armor to gain the unique item needed for the schematic. Then head to the armoury, (southeast in the camp) to commission the crafting of the adjusted Calida's Hamata.