I saw that on Sensorly, too. I was there just moments ago and there appears to be something going on. At 32nd St and Cactus, I picked up LTE for about a minute, by the time I stopped the car and pulled up Sensorly, it reverted me back to 3G. I drove about 2 mile radius around this point, resetting my data connection as I went, and I connected to 4G a couple times, but again, I was reverted back to 3G. They must be testing a site in the area but, blocking its use to the end user, or something like that.