I had been running a GSM unlocked XT907 for service through Net10. After installing KitKat over-the-air, I've not been able to get any cell reception (WiFi works fine). Factory reboot, reflashing 4.4.3 had no effect; I generally can't detect any available GSM or CDMA networks. I've tried a few locations in downtown DC, and briefly got one bar long enough to download a few text messages, so the settings still seem correct. Any ideas what could have ruined my reception?