For far less money you could have radios that work without infrastructure at all. What range are you trying to cover?

LTE range is terrible so you need a very close tower that is still on and connected to the core. Cell companies spec for 30 minutes of backup power being a big site that has high redundancy. Roaming is already a thing. If this radio worked, your cell phone would have worked. If your only use is emergency prep these are just wasting money.