So I bought an iPhone XR not to long ago and had it on T-Mobile. I then switched to AT&T Prepaid when the $45 unlimited everything with autopay deal was going.

The other day I went to a Corp AT&T Store and tried to get a Esim activated but they refused stating that its not allowed and the stores that are doing it don't realize people get cut off within 30 days due to the system finding out.

I then asked to do a sim swap so they swapped my AT&T prepaid sim with a regular orange sim and I asked if there was a charge and the rep said there was not so I walked out with a completely free sim.

Anyways after I walked out of the store and got to my house I did a test call to see if everything was working and that's when I noticed my iPhone XR was staying on LTE during the entire call. At first I thought it was a glitch but during some of the calls It did sound much clearer than usual and everytime I call now "LTE" stays on during the entire call. WiFi Calling is still not available.

I suspect that maybe when the rep was on his iPad, his system asked to enable the feature or AT&T could just be testing on select accounts/iPhone's at this time. I did notice AT&T recently did some work in Portland, OR and LTE speeds are faster so it could be a trial run.

*Note: VoLTE on AT&T works on all iPhone's 6 and up and also AT&T Branded Phones only. AT&T VoLTE is not available on Unlocked BYOD devices that are not AT&T VoLTE Approved.