I think I spotted a bug in the recruitment after the Polybian reforms.

I built a Tier 1 factional MIC in Segesta AFTER the Polybian reforms and was able to recruit Accensi, Leves and Rorarii.

After upgrading to tier 2, I could recruit the Accensi and Velites

Tier 2 and above look fine, but tier 1 still has the Camillian units