[Imp]

I agree for a diffrent reason that reinforcements arriving by the formation leader would be a bonus. It would make the random arrival time feature usable. At the moment using it platoons can appear before there leader or support units before the rest. Say the MG unit turns up but no squads.
For scenerio design though & probably not possible placing trigers would be best with a selection of choices.
Keeping it simple
Reinforcements arrive, or selected units have there reaction time reduced to zero & hence advance.
Would give a lot more control over the AI for say ambushes rather than try & guess what the player will do.