Thanks Dave, I'm slowly cranking out more battle reports as I play them.
You are correct, this rule is changed in Revolution. Revolution primarily uses the Warmaster Ancients combat system.
Page 44 of the Warmaster Revolution Compendium, 5th Paragraph entitled "Supporting Combat";
"Units are automatically included in any combat engagement where they support. This means they are affected by the combat result and the usual options apply. This is covered in the following sections under Retreats and Winner Options."
So supporting units count as "in combat" and therefore, for example, they cannot be shot at, and must retreat from the combat they were supporting if they lose.
This makes it far more deadly to drop flyers in behind supporting units, as they can potentially take out an entire undamaged unit by blocking a combat retreat.
Iain