I've read a few other members with the exact same problem. Edge will need to put out a software upgrade to the CTS, I'm not sure if they've done it yet.
Yea, it seems to be more common lately. From what I'm reading, they don't have a fix yet right? They keep flushing the coolant tanks and not really finding the root cause of the problem.
They make a DO NOT FLASH OBD cover you can put over the factory plug.. it means no guarantee but it's better than nothing.
Besides instructing your dealer not to flash I'm not sure what else you can do.
Did the turn get it or is the jack just to close and the tailgate sit down on top of it?
Same thing happen to my father-in-laws truck.. But, he just sit his down and it got it.