I've never had the hydraulic system, I have the electric Lippert 6 point auto level system. I think the hydraulic system works similar.
But what you do is, after you unhitch (trailer is still high in the air to clear the truck bed), you simply hit the "auto level" at that spot. The auto level will level the trailer and enjoy your camp out now.
When hitching back up, to retract the jacks and to return to the same spot in height for hitching, you hit the left and right buttons at the same time.
On mine, the 4 rear ward jacks will start to retract. Once they are up a little bit, the front landing jacks start raising to their original position when you unhitched.
However, if you were parked on soft ground, sand, or dirt, it's possible the trailer tires and jacks could have sunk into the ground some. If they did, your original front king pin height will be lower than the original position and then you still have to manually raise the front jacks a bit more to clear the fifth wheel hitch and hitch up.
But to return to the original position, the original position is wherever you hit the auto level button. That's were the trailer will return to.