I noticed recently that when doing a level 100 defense mission on the priority assignment (Grim Penance) that the generator defense target has 5000 hp, which is what a level 4 one has when doing a defense mission in the tutorial section. Except now the enemies are attacking with level 100 attack stats, and basically can shoot it from off your screen and actually outside your minimap ping range as well. I kind of wonder how melee people even do this one since a couple of the fireball shots will destroy it, and they can shoot off the screen at the target.
However, the Guardsmen seem to have the proper 21000 or so hp. This also didn't happen during the Prophecy campaign, where you have to defend some cogitator, if I remember right.