Same problem here. I just got 2  x Era 100s to use as a stereo pair. They work fine with YouTube Music, or Airplay from iPhone, but will not work with Apple Music Service.  Just like you describe in the Reddit thread, it will try to play but just skips through a few songs without playing anything and then stops. 

Any help, Sonos? 

Update : Tried again after an hour - suddenly Apple Music Service working OK !

I am having the same issue. Just hooked up the Era 100 to replace my Sonos One which I moved to another room. Apple music works fine on all of my other devices but will not play on the Era 100. Connectivity is not an issue and other apps such as Sonos music, amazon music, etc. play music just fine. When I attempt to play on apple music, the track keeps skipping forward and will not stay on a single song. If I start the music in another room, then add the era 100 it plays the shared audio just fine. I have always had good luck with Sonos in the past but I am guessing an update is needed. 

UPDATE: Not sure if the device needed some time for the update to complete but Apple Music is now working properly.

I’m having the same problem with my two brandnew Era 100. Apple music not playing in the app. keeps skipping from track to track without playing anything. Renewing authorsation doesn’t help. Playing apple music over airplay is no problem. 

Just give it an hour and see if it works. It did for me. Seems to take time to set itself up.

Same here. Chat pointed me to this thread (thanks Alexandra 5!), but as short-term workarounds for others landing here Airplay continues to work, as does grouping the new Era 100 with any other existing speakers. The problem is independent of the new software - I have new and old on different devices, but no difference.