Thank you very much for the answer. I was under the impression that the Polybian reforms occurred during the First Punic War.

Your answer leads me to another question though. How exactly were the maniples equipped?

This is based off what I have read, EB, and other mods:

Camillan
Rorarii - Scutum. Did they throw javelins as well as carry spears?
Hastati - Scutum, greave, Monteforino helmet. This is where it gets tricky - some mods give them only spears, some like EB give them short swords and pilae
Principes - Scutum, greave, breastplate, Monteforino helmet. Everywhere I have read the Principes had spears

Polybian
Hastati - Same as above but do they have a breastplate now or do they have chainmail? They would obviously have pilae and a gladius
Principes - Same as above but they had chainmail as armour. They had pilae and a gladius.

If the Hastati had chainmal, wouldn't they basically look the same as the Principes? In that case instead of having Hastati and Principes, shouldn't they be combined as a Polybian Cohort of some sorts?

If you could clear this up for me it would be much appreciated!