Say you have an army of 3 corps in region a and want to move the army headquarters and two corps into region b and leave 1 corps in region a.
You can't use synchronize movement into region b, because all 3 corps would so move, therefore you would need to move army headquarters and 2 corps individually into region b, or first detach a corps from the army and then use synchronized movement. Is this right ??
I'm really having trouble working this out.