HomePod is not yet available in Italy but Apple has released the first software update that aligns with iOS coming to version 11.3.
Internally, the HomePod operating system is called “audioOS” and is a modified version of iOS. The firmware weighs 2.36GB, the build is 15E217 but unfortunately, in this version, only minor bugs are fixed to improve overall stability. No support for AirPlay 2 has been added, which is also absent on iOS 11.3.
How to update
Make sure the HomePod is switched on and configured. Open the Home application on iPhone, click on the location icon on the top left and go to Settings> Speakers> Software Update. The update also takes place automatically in the background.