When a Unit Dies
Immediate removal, immediate recalculation.
A killed unit is removed from its stack immediately. If it was the last unit, the stack is disbanded. If the stack still has survivors, its combined stats — total HP, firepower, speed — are recalculated from them at once, and the dead unit's pending reload simply disappears.
Whatever it carried dies with it: passengers aboard a transport, missile and ammunition cargo in its hold, carried gear, and any transport order it was running. Any loading bay it held is freed.