The stiffer springs ended December 2017. The improved rear seats were around May/June 2018. The front seats got changed, but not really improved - the stitching changed slightly is all. The rear seat improvement actually added some cushion on the sides. I was a little pissed at the time, but now realize after a year+ 1) I've never sat back there, and 2) I rarely have other sit back there. And if they do, they don't know better. haha.