Hi @SouthboSonosGuy
I understand your concerns - resetting 20 devices is no mean feat.
I do not recommend you reset your entire system in one go - that will result in more work. Resetting one (or a few) at a time and adding it/them back to the system before resetting any more would be the way to go. This way, music services and some other settings will be retained.
As for if resets are needed, we’re still waiting on hearing back from customers like you, to be honest. AirPlay and HomeKit are Apple properties and we are not aware of what, specifically, went wrong with the last version of HomeKit- only that it was pulled from Apple’s download page because of issues with various brand’s devices. I’m not an Apple owner, so I’m not overly familiar with HomeKit, but I hear that you can deregister devices within it - I’d certainly try this before resetting the speakers.
Although there is a tiny risk with each factory reset, the main reasons we don’t want people doing it when not necessary are 1) environmental problems (like interference) aren’t fixed, 2) it needlessly creates more work and frustration, 3) if there are network problems, you may not get it added again, 4) it erases all the logs of what actually went wrong. These don’t really apply to the AirPlay/HomeKit problem.
Contacting Apple may reveal answers - maybe they even have a tool that will fix whatever data AirPlay receivers are holding on to. I don’t know if all the other AirPlay compatible devices from other manufacturers need reset too.
Ultimately, I recommend you try with one speaker - if that works, and if you couldn’t get it to work any other way, you may have to reset all your AirPlay compatible speakers - just not all at once!
I hope this helps.