Welcome to Canon World. They have a long and deep history of stranding customers, including heavily invested professionals. I am sorry that you had that experience, but to tell the truth, this is not an uncommon story with Canon, which is why I don't support that company by purchasing their equipment unless its absolutely essential for the project, and even then I liquidate that gear as soon as possible afterwards. You may want to do a search on the site 'Sportshooter' for an independent repair shop, those guys have had plenty of experience with long tele's that are not supported. I mean can you imagine getting a 400mm 2.8 or 600mm f4 and not being able to fix it? Makes a nifty paperweight.