Slitherine

In a user-made scenario, how to make the AI side play first ?

I want the IA to move first.

In custom AI data dialog, I turned Aggression to 16 and located target AI points behing the player's army.
I now need the IA to play first.

Possible ?

P&S AI tends to advance toward the player army, even when starting on a hill and thus having a potential Uphill advantage, right ?