I did some quick skimming on the state of Sailfish US connectivity in early 2024.

5G support will not work on 10III for T-Mobile. 10III 5g bands: n1, n3, n7, n8, n28, n77, n78 T-Mobile USA 5g bands: n41, n258, n260, n261, n71

however, 10 V adds the band n41, so we will EVENTUALLY get SOME 5G coverage

Xperia 10 ii on US Mobile or other T-Mobile MVNO is your best bet.

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