Halo sag. I brought this to attention in the link above several years ago.. Seems to be common. I believe the heat from the turbo and engine are to blame. Yours is definitely worse than mine. If you can get it reduced by playing with the bolts great. You might be able to get that part replaced with a new one but expensive and the problem will just occur again. I have been raising the engine hatch after driving to help dissipate the heat until the engine cools. Seems to have solved the problem as mine has not gotten any worse. Good luck!