When I talked to them, I had to talk to three CSR's and a tech, and they kept saying that there is a "backlight" issue that is going to be fixed via the .604 update. I then told them that I am not having the "backlight" issue they were describing, but rather that my screen was flickering at intermittent times and that I didnt want to take a chance with it after my 30 days were up. I told them that this is not an isolated problem, and that many other users have already placed orders for an exchange, etc. I told her there were many forums and videos discussing the screen flicker issue. At that point, and after searching her own sources, the CSR said we will send you a new phone under the "worry-free guarantee." She said that I could send my old phone back when I get the new one, so you should request the same thing. Got my order number and just waiting now until 7/27.
Hope it helps! I would be stern but not rude obviously. If they mention the "backlight" issue, tell them that that is not the problem you are having, but rather your screen is actually flickering (they couldn't understand the diff when i was explaining that to them lol).