I have my home router setup as 192.168.178.0/24 and it contains most of my home devices including Sonos. This router is connected to the WAN port of my Beryl (MT1300). The Beryl has a VPN running and policies to direct traffic by domain.
The issue I’m having is connecting to my Sonos devices when i phone is logged into the Beryl’s wifi. There a lots of (for me) incomplete and confusing OpenWRT posts about how to set this up, but none that i have been able to get working.