The case you show is really peculiar and is the consequence of an event, named "Schulmeister"...
The event makes the whole army under Mack fixed for 1 turn, usually at the end of the first game turn (to represent Mack being misinformed by French spy Schulmeister and tergiversating for 1 week in Ulm)...
The fixing is removed after 1 turn in all cases... now we can remove the event, but I like the "spice" of it...
... for one more reason, we have also scripted the fact that if the French army manages to get in between Mack's army and Austria (at least 4/5 units in the 3 regions east of Ulm, plus a few forces in Ulm itself), then general Mack has a chance to behave historically, i.e. surrender.... the player will see an event triggered called "Ulm Maneuver"...
May be it is a bit "heavy" on the player, but I liked the chrome and historical aspect of it... and the challenge for the Austrian player to escape that death trap (there are ways
)....
But we can also remove all of these...
What do you think