"I've also heard that the unlocked unit will support voice-over-LTE and Wi-Fi calling on all carriers. AT&T, especially, tends to be testy about allowing those features on unlocked phones, citing software compatibilities. But the carrier says you should be good to go with this one."
Cool, I guess I will test it when I get mine. Just to be clear, Note10 and S10 technically support it too, but it is AT&T that choose not to allow it. No idea why.
@userceCMC3weqT I was able to test this out at the unpacked VoLTE did work on AT&T for unlocked, however, I didnt see wifi calling option but since it is VoLTE certified on at&t you can flash AT&T firmware and wifi calling should work!
Yeah, I went with the AT&T model cause I didn't want to lose any of the carrier features.
The first 24hrs with my S20 Ultra and I can confirm Wifi Calling doesn't even show up. I have a case open with AT&T to hopefully resolve the issue, but more than likely I will need to exchange the phone. The Samsung chat and phone support say that AT&T is blocking.
i bought the S20 Ultra unlocked because of the article I saw on PC Mag. Guess what? Wifi calling did not work on ATT network. I switched the ATT sim with my other sim from Verizon , Voila, Wifi calling showed up and so did Voice over LTE. ATT continues to block WIFI calling for the unlocked Samsung.