[Mobhack]

Also, the HE etc buttons are set to "invalid" if the target X,Y is out of range.

With mortars etc, I usually click on a few hexes past the intended impact zone to see if I'm on the edge of the units range and hence scatter may take the weapon out of bounds. If so, I can use a closer one. If i think its ok, then I plot on the intended target.

Although the game happily allows you to adjust the impact hex to out of bounds, some day I may look at that and try to fix it, the arty plotting being some of the nastiest tangled spaghetti in there.

In any case being able to adjust if it has gone out of bounds to put it back in is probably better than disallowing adjustment since it often results in a lesser break in firing. So on second thoughts - it stays as-is.