Well obviously something is moving, has to be. The front suspension on these cars is pretty simple in reality and in order for something to change, something has to move. As to the ride height, this is set by the adjusters in your lower control arms (applying tension on the torsion bars). I highly doubt they are moving my backing up and going forward (would not affect them in that way). Therefore, it has to be something else. The only way (I can think of) for the ride height to change are:
1. the adjusters are moving (no likely or even possible in this scenario)
2. something is forcing the lower control arms down (thus raising the car), this would have to be some extraordinary event as that would take a lot of force
3. your torsion bars have issues, either slipping in the LCA or the cross member where in they are loosing tension in once instance and getting tension placed on them in another. Here again, I don't see how that could happen but given the suspension design not a lot of options.
Have you driven it after the alignment shop was done and see if it settles down?