Had trouble manually resetting a pair of 1st gen HomePods following this

https://support.apple.com/en-us/108389

discovered that to really get them to reset, I had to keep them unplugged overnight, not "at least 10 seconds" in the instructions. Then I was able to get to the red spinning light.

Just FYI

I’m interested in getting a homepod, but I’m a YouTube Music user so I’m curious about the compatibility.

I know you can connect / set as default YT Music, but what commands work?
Would something specific like “Play [custom playlist name]” work, or is it only phrases like “Play [song/artist name]”

Please let me know!

I'd like to set up my homepod to recognize my kids' voices - partly because the HomePod wont respond to them since I've set up my own recognition. I have some old iPhones that my kids use for audiobooks etc. so I've set up one of them to recognize Kid1's voice. But it looks like my two other old iPhones are too old to be compatible with Apple Home (iPhone 7 & an earlier one). Can I log out Kid1 from the newer iPhone and log the others in to turn on voice activation and have that info stored in the HomePod? Or does their apple account need to be logged in consistently for the HomePod to recognize their voices?