This is my solution and it works for incoming calls. I have a Google Voice number and I forward my Xfinity Mobile # to my Google Voice number. If I need to make an outgoing call and I have no signal I use my Google Voice number. Let’s face it, I pay $2.53 a month for unlimited calls and text messages. I use no cellular data and use WiFi only on my iPhone 6. My main concern are emergency calls from family. So, Google Voice takes care of that.
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