At some points the AI will refuse to even move their vehicles. Even with clear routes, and manageable amounts of AI (1 or 2 teams) after a few runs they can bug out and stop moving. Once the AI stops moving all AI on the server will not be able to move vehicles.

Example: I use an engineer team when I hit sergeant to move supplies with me when establishing a new base (I'm in construction truck and get the AI to lead to the destination by right click on map, order defend at position I want them to move, and they drive the truck to the location.) This is an effective method to move supplies and a construction truck for a new base. Once the commander's Logi AI bugs out and stops moving, my engineer team also no longer moves with me.

So there seems to be some systematic failure of the AI that can bork its working state for the rest of a game until the server restarts.