So I should turn on airplane mode when I’m making calls on WhatsApp to SXM using my house WIFI here in the states?
NO.
But you could if you wanted to, just not required. At times at my house the cell service is weak, and so wifi calling works better.
Noting we are here for multiple weeks this time of year, I just pay for the one month subscription at $100 (discounted since a business customer). It automatically stops at the end of one month and it is less hassle than other options to us. I also carry a T Mobile phone that I use to hot spot at times when I need a private network, works well for us. T-Mobile does work better here than Verizon in my opinion, but Verizon is much better in most of the US.
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