Could simply be each individual player being counted as a profile and so you're hitting the group limiter. The group limiter is a very inelegant way of restricting the number of spawns, as you are discovering. If you want to keep the numbers manageable, it's better to spawn fewer in one place or spread them out more. Use TAOR sizes to manage the density of your Placements and give the AI Commander plenty of Logistics so he can keep the numbers up. The Group Limiter is like a 'hard deck' to prevent accidentally spawning in the whole world when a helicopter flies over and killing FPS. CQB units and Civs are not counted, so you can still get a lot of AI in one place if you're running those as well (though you can and should put CQB on Headless Client).