Same issue. 2021 JLUR. Built August 2020. It’s 6am here and rainy and cold, and I just pulled out of the parking lot and it squeaks at every brake actuation. I even stopped hard once to clean out the water on the roof and the rear squeaking was crazy. Mine also squeaks sometimes even if it’s not cold outside. I really want to narrow down the noise because it must be a specific suspension component making it. I first assumed it was my driver-side spring but who knows.