Copied turrets are remove from the undo/redo queue when placed.

To do with the turrets ghosts being placed.

The control.lua will replace all turrets with their lowest (unleveled) base turret in case of copying/pasting veteran (and non veteran) turrets.

Will need to look into the undo/redo stack and most likely needs the eyes/ears of Wube and the Factorio mod forum to seek the route for a fix.