Twice now, after adjusting connection preferences and priority devices in the Deco app (trying to optimise the Sonos network), internet access has completely dropped. Devices stay connected to Wi-Fi, but there’s no internet. I can directly connect to the ISP's modem which works fine, so I'm confident it's not a modem or ISP issue. 

Power resets would occasionally bring back a small burst of internet for a minute or two, but then internet ceases altogether again. Reverting the settings above did nothing to fix the issue. Only way to fix was to factory reset both hubs and setup from scratch.

On the third setup, I have avoided touching these settings and now the network remains stable, but it's not ideal that I can't attempt to optimise the network or use various features of the hub/app.

I've searched and haven't heard of others facing this issue. Has anyone else had this happen? Any known fixes or firmware updates that solve it? Trying to avoid going through the full reset process again.