You mean using the ELC system to lower the car, or lowering it while still having ELC functionality?
ELC is rear only. The stock rear springs are soft. They retain proper rear ride height, only with no extra weight in the car. When weight is added, the rear sags, and the bladders are inflated to compensate.
No. As posted, the coil springs will keep the rear at proper ride height, without the ELC system. IF you have WORN SPRINGS, and let air out of the ELC system, the rear will lower. Add a passenger or put something in the trunk, and it will get even lower, and bottom out over bumps. The rear springs, as posted, were not designed to handle any extra load by themselves.
Even if you could use the ELC system to lower the car, ELC (again, as posted ) is rear only.