Well, your tuner can likely go up to channel 69. Either way, even strong out-of-band interference can mess up a tuner.
Most cellular antennae in urban areas are at least 10 degrees down from horizontal. So this makes sense. It's the incredible ERP that doesn't make sense. Think about it: Most hand held devices put out 4 watts maximum. What's the benefit with having such a disparity between the tower and device?!
I agree that such high power networks should not be deployed in residential areas. No doubt your neighbours are experiencing interference as well. Have you thought about posting a notice to get people complaining about it?
DMX 68' tower, HyGain HAM 5 rotator, Antennas Direct 91-XG & C5, Channel Master 7777 preamp, Siemens surge protection