After welding their is stress in the frame.
Apparently the stress is shifting on some units.
Have you ever seen a cookie sheet or a pie pan pop/twist when it is in the oven?
That must be what is happening to the suite frames. And they are not popping back into shape.
Lippert needs to either thermally or vibratory stress relieve the frames while in the manufacturing prossess to correct the problem.
There engineers should, but might not know this.