Option 2 is not really doable, but luckily it's not necessary anyway, like Sasaki explained.

As for 1, I think the only times ranged units change their position is when you ordered them to fire an enemy unit and it walked out of range without routing. Then your unit will do whatever is takes to keep firing - so, it may change direction if the enemy is walking to the side, or chase the enemy when they walk out of range.