I cant see Airplay option for New Apple Music for Windows. Someone really forget about it ?

Bingo, this fixed it for me.

1. Close Apple Music
2. Ctrl + Shift + Esc to bring up Task Manager
3. Go to the Services tab
4. Look for Bonjour Service
5. Right-click, select Start (mine had been stopped)
6. Start Apple Music
7. Play any music

You should now see AirPlay in the top right between Volume and Lyrics controls, with all of your HomePods/AirPlay devices accessible. If not, make sure you are on the same network as them.

It seems one of the Apple Music updates does not start Bonjour properly; if it's not running, you will not see an AirPlay option.

Have been using the Windows app for a couple of weeks. Relaunched app today, and AirPlay icon is missing. Anyone else seeing the same?

I know *exactly* what you're talking about! Here's what I've been experiencing, running the new Apple Music client on my Windows 10 PC:

I’ve noticed that the newly released Apple Music client for Windows (which replaced iTunes a couple of months ago) no longer supports AirPlay to Sonos (or other devices) for any files downloaded from the service via the Apple Music subscription. 

You can still AirPlay to Sonos while streaming. You can AirPlay any songs you downloaded via the old iTunes client (or any MP3s that you access through the new client). And you can Airplay songs that you purchase from the iTunes store and download. You just can't play files that you “add” and download to your PC using your subscription via the new client.

Seems like they either forgot to support that particular format - or intentionally left it out for some reason or another. SUPER frustrating though. I frequently AirPlay to my Sonos devices from my Windows PC, and now can't do that with any of the music I've recently downloaded. The only workaround I've found is to "Remove Download" for any of that music. The minute I do this, boom - AirPlay is re-enabled. Not ideal.

Make sure Bonjour is running in services.

Thank you!

Oh my God! This is the only true answer! Thank you so much!

See the 'If there’s a problem with an AirPlay device' section in:

Choose which speakers to use in iTunes on PC - Apple Support

The AirPlay button  should be at the top of the iTunes window.

AFAIK, iTunes is how you access an Apple Music subscription on a PC:

Listen to music and more in the Apple Music app - Apple Support

Join Apple Music on your iPhone, iPad, iPod touch, Mac, or PC - Apple Support

unless you are referring to web access:

Listen to Apple Music on the web and in apps - Apple Support

At present, there is only iTunes for windows. The Apple Music app for windows is in beta and features may/May not be available until a final release.

Hey they fixed it!