The upgrade paths are a bit strange. It seems not only to depend on your phone, but also your mobile network operator. Or at least that's the situation in the USA, but I'm not sure how the technicalities are handled in Europe. I remember my last phone suddenly popped up a note about a new version being available, so there definitely is something in place to handle it, but how exactly it works I have no idea... You can also probably update manually but that might be voiding your warranty. So if you want to be absolutely sure, it's probably better to wait a bit longer and get a phone that has the newer version out of the box.