TDS Mobile Reliability??

We use TDS fiber, it's been great, especially because we have another cable company in our town so we are locked in at $63/Mo for life with 1Gig. They now have TDS mobile. This is the first cable/ISP mobile service to my knowledge that doesn't use Verizon. Ironically, we have horrible Verizon coverage here and had to switch to ATT, which is great. I'd love to save $900 per year on the same service but always worry you're getting the "B Squad" network and I wouldn't have the same service/coverage even though it's still ATT. I feel like ATT would prioritize their network for their main customers first, no?