Quote Originally Posted by Bob the Insane
I think it depends on how much fighting there has been... I don't think the Roman Ai factions will disband any existing units on purpose, but if they are fighting loads then those pre-marian units will eventually get all used up...

I have seen the Brutii if full stacks of legionaires and other post-marian units in my last scipii game, whereas in my present Julii game where pretty much all of my pre-marian units have been recycled into legionaires, but the SPQR faction is still all pre-marian units...

I think bob's got it there, the ai will certainly build new decent units as they expand or their existing units are killed off. However I don't think the ai will disband an outdated but full strength unit and replace it with a new unit. So if the roman factions stop expanding, they will undoubtably end up with outdated units. The senate which i've never seen fight a battle obviously therefore ends with the army it built in the first few turns of the game.

Has anyone seen the ai retrain a unit?

If so maybe making pre-marian units retrainable in post marian versions would solve this.