1.) With map editor I created 4 default rifle teams consisting of several individual AI units.
2.) Change the rank of the squad leader to 'major'
3.) Add a single unit as player.
4.) Change the rank of the player to 'colonel'
5.) Preview game. Result: Player is not in control of AI units.
6.) Per drag and drop units are now directly assigned to the player. Resulting in 30 individual AI units under the player's command. Now I would assume that the automated teambuilding feature will organize the units into teams.
7.) Preview game. Result: Player has 30+ AI units in direct command. Without any teams and chain-of-command. Orders have to be given to each AI unit individually. Grouping into red, blue, green teams has to be done manually.