A few minutes after the 8.2 upgrade finished (ATT iPhone 6) and rebooted, I was reading an iMessage from a buddy and the whole screen went black with a message saying my SIM had sent a text. I was able to quickly screenshot it before it faded back out. Did anyone else experience this? I found a short thread via Google on Apple's Support forum with one guy saying he had the same and called ATT and was told his SIM is failing, but nothing else besides that.