The devices section will be coming back in a future update.
In the meantime: You won't be able to see an indication in the desktop client that the device is paired with the desktop client. But as long as they both are on the same WiFi network you should be able to trigger the local files sync by toggling the offline toggle on the playlist on your device. Just make sure that the local files are in a playlist of their own so that this will work.
View the help guide on how to sync local files to your phone:
Using the desktop app, add local music files you want to sync to a playlist.
Log into Spotify on your iPhone using the same WiFi network as your desktop.
Tap the menu button ().
Tap Your Music.
Tap the playlist containing local files from your computer.
Select the playlist containing the local music files and press the Available Offline switch at the top.
A green arrow will appear next to the tracks when syncing is complete.
MattSudaRock Star 24
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