I've always recommended rotating tires every other service, but now with how service intervals have changed as oil technology improved, I tend to stick with every 7500 miles for rotating, and every other rotate gets a balance.
At least that's how I do it in my shop (Jaguar / Land Rover dealer)
Has it been exposed to any chemicals?
I am currently going 5 rounds with Ford because ALL My door handles / bed caps / wiper cowl / fender vents / rear bumper cover plastics have faded. They tried claiming its wax, but it's not. When the truck was new and ceramic coated, all plastics were...