Without much fanfare or pre-announcement, the IOS 10.2 update released earlier today finally enabled WI-FI calling for Telus customers. 

After installing the update, the device rebooted. I then enabled WI-FI calling by:

Settings > Phone > WiFi Calling > Toggle ON

WI-FI calling means cellular calls could be routed via a WIFI network in areas with poor cellular coverage. When the phone detect low cellular connectivity (aka reception dots in the upper left hand corner), it will route inbound and outbound calls with WIFI. 

As soon as I enabled WI-FI calling, I received an email from Telus with this new "free" option automatically added to my line.

Telus support said VoLTE (Voice over LTE) is coming but couldn't give me a date.