I initially didn't include artillery when I opened up this mod for cars, because artillery tends to be not essential to a base defense. If it has no ammo, you are not clearing enemy bases, but your factory is not in danger of being breached because of it. So if empty artillery is no problem, alerts become unnecessary and annoying.
Fast forward to now: I added toggles to disable car alerts or turret alerts, so there should be no reason not to add an artillery one in the next update (when I find time to work on this...)
