The problem with WIFI calling is that Verizon no longer allows the option for most phones to force WiFi calling.   So if your cellular signal is only one bar, it will still connect with mobile.   This is the whole reason I got the extender.   If at least they would allow white listing, then I could leave the extender on for my Pixel phone and not interfere with the iphone.  I wish Verizon would escalate this to their technical geeks.