yes, working, you need to add some code in build.prop file every time when you do an OTA update.
the code is available in this thread, search for it, you will get it.
volte will not show in status bar after adding the code to buidld.prop. but it works.
to test it, turn on the data & make a voice call, if data is not disconnected during your voice call, that means VoLTE is working.