I always wondered what would be approximate date when 'polybian' reforms happened in real life? Concerning Marian reforms; we can connect that to time when Cimbri and Teutones rolled over Romans in Arausio, and Jugurthine War.
I have doubts about Polybian reforms, though.
One of conditions is that you must conquer Sicily, that would place reforms no earlier than 212. bc.
However, I also think of end of First Punic war. I just cant imagine aspis bearing Triarii in battle of Cannae.