WiFi Calling (iPhone 11/Verizon) and IPv6

I have eero installed in two separate homes. In one home, I have been experiencing all incoming calls going directly to voicemail when I am on the WiFi network. I suspected this was an issue with WiFi calling, so I disabled WiFi calling and tested, and calls began coming through.

At this point I was trying to figure out why my same device would have problems on one eero network and not the other, so I took a look at the configuration for each. In the home with the issue, IPv6 was enabled. I re-enabled WiFi calling, verified that calls were again going to voicemail, then turned off IPv6 and tried again--the calls went through.

Would love someone from Eero support to take a look and determine why IPv6 would interfere with WiFi calling (I am using an iPhone 11 Pro Max and Verizon).

Thanks!