Is being spotted tied to a specific spotter, or is it a general status/mark?
What I mean is, does it work like this: once a spotter sees your unit (or is shot at by your unit, or wounded by it, or killed by it), your unit is visible to the enemy snipers for the set number of turns, no matter what happens to this specific spotter? That is, if, e.g., a Master Spotter spots your unit (which apparently makes your unit visible for the rest of the battle) and is then killed, will your unit still be visible to the enemy snipers until the end of the battle, even though the enemy who has spotted it is long dead?