Hello Alex,
I appreciate the response you gave to this question above. However, I was told that MetroPCS is part of T-Mobile US, so wouldn't Wi-Fi Calling work regardless on the iPhone 6s. It works on the iPhone 5, 5s, as well as the iPhone 6. Not only it shows the Wi-Fi Calling option, it even gives the user the ability to update e-911 address on device. I've also noticed whenever I try updating the carrier settings on my iPhone 6s, it gives me error code: 1630, could this be another reason why Wi-Fi Calling isn't functioning properly? It seems like the iPhone 6s doesn't recognize the ICCID or "SIM", therefore, it goes into Global Mode, aka "Generic Mode", as if MetroPCS isn't a partner carrier. I'm not trying to debate what you're saying, however, this is an ongoing issue with many iPhone 6s users who have MetroPCS service, such as myself, who are trying to get to the bottom of this issue. Thank you for taking this time to read this and I hope for a response from Apple engineers to resolve this issue.
According to this link shown on the Apple website, it shows MetroPCS can receive Wi-Fi Calling on any of Apple's iPhone devices, even the iPhone 6s: Wireless carrier support and features for iPhone in the United States and Canada - Apple Support
Metro PCS
- FaceTime over Cellular
- LTE
- Personal Hotspot1
- Unlocking3
- Visual Voicemail
- VoLTE4
- Wi-Fi Calling
The above is an except taken from the above link.