Had to bring the car back for the under tray bulge. They didn't give me a hard time, but it wasn't ideal either. First they took a whole day to check the tray was indeed bulging (I still feel like you could check that while talking to me, but anyway). Then they had to order the part from across the country, which, although not uncommon for us, is a nuisance.
They day of the fix was also a little bit sub-par. I had asked if the car would be ready by 3.30 pm (I work school hours), and they promised the car would be ready for 3pm. Sure enough when I get there at 3.25 pm the car was "almost finished". Dashcam footage showed the car not going up on the hoist until 3pm though, a little disappointing. At least it was all free I suppose, and I had a nice talk with my Uber driver.
All in all, I'm just happy I don't have to fight my dealership about everything like a lot of the UK people are reporting.