No question here, just a warning. After restarting my BT Whole Home wifi mesh system, I found that two players (one on Ethernet, one on Sonosnet) were missing from my iOS Sonos controller app but could be seen in the PC desktop controller. I had also power-cycled the players, and indeed all devices. So there was no obvious culprit.
Both players had valid IP addresses though, and were on the network. I eventually worked out that the Whole Home system had restarted with some paused / blocked devices. I had unpaused the wifi ones - but had no idea that it could even see the wired ones (if you drill into the app though, this becomes apparent on the Devices page). And while it obviously can't block wired (or sonosnet) devices as such, it can purport to do so and this stops them being seen by devices on its own mesh.
Coupled with this, a growing literature on other forums also suggests that BT Whole Home accidentally blocks devices quite regularly - personally, I suspect mostly through operator error (l'm assuming that my thumb brushed against something). It seems that blocking doesn't always come off when you ask it the first time, though, so sometimes you have to toggle it a couple of times.
Of course the blocking feature on mesh systems is primarily sold as a means of blocking wifi-connected devices, such as children's phones and tablets at meal or bed times. So this essentially undocumented and unadvertised "feature" took me ages to figure out. lt would never have occurred to me that my mesh system might appear to kill wired (or Sonosnet) players simply by preventing them from being seen by wifi devices that were themselves fully operational.
PS - I still recommend Whole Home, but this feature should be advertised!