I have a Netgear Nighthawk Mesh system that I setup to take the place of the wireless from the Verizon router (they are my internet/tv/land line carrier).  Due to some tv problems, I ended up getting a free upgrade to the Verizon equipment and it seems to make the wireless network from my mesh system require everything to reconnect.  Our Sonos system is four Play 1 speakers, each running on our WiFi. 

So when I went to reconnect the Sonos system I had a number of problems with the Sonos app on my phone telling me that at times, it could not find my system or specific speakers, etc.  At times it said something about checking the wireless network that my phone was on.  After trying a number of restarts for one day I factory reset all the Play 1s and went off to think.  The next morning I started as a new system setup (which I had tried before) and then still had some problems finding equipment and getting message asking me to check the network.

I then thought about my phone - which is a Pixel 6 with Google Fi as my carrier.  It occurred to me that Fi does automatic switching back and forth between the cell carrier to WiFi for calls and data.  So I put my phone into Airplane mode but with WiFi turned on.  This seemed to reduce the number of error messages I got.  I still found that occasionally cycling power on the Play 1s and the mesh router was helpful between adding each speaker back to my system, but all in all, it seemed to go fairly smoothly - much better than the previous day - so I think having the phone in airplane mode reduced the confusion that the app was running into when searching for speakers.