I first noticed my headliner was wet on 3/21/19. I have a 19 RST and I have the same issue with the leaking rear window. My headliner, and rear seats were soaked. I suggested the check Bulletin 18-NA-383. The dealership resealed the back window, replaced the headliner and rear seat covers and cushions. They had to remove the windshield to get the headliner in/out, while doing that they damaged my dashboard. After pointing out the dashboard was damaged it was replaced. After trying to reseal the window two times they decided to replace the entire back window. Picked it up on 7/3/19 lets see if the window stops leaking