8.23 Special observation powers

[plloyd1010]

Apart from saying recon units may spot an enemy unit in limiting terrain once per turn, there is nothing said about the mechanics or timing. When would this happen? Could it be before or after an activation? Would it be an activation of the recon unit?

Say I have an AT gun, the bad guys have a tank 5 hexes away in a woods hex, and I have a recon unit able to observe said woods hex. Could I declare the tanks spotted by the recon unit, then activate the AT gun to fire to fire and blast the tank? It doesn't sound cricket to me, but there is not a prohibition either.