4.1.2

I have a Samsung Galaxy S3 Mini (GT-I8190n) and it is running Android 4.1.2, I am with Vodafone in the UK. I am fine with this but I have one question. My friend, also with Vodafone just got the same phone as me (GT-I8190n) but his phone in on 4.2.2, I have looked everywhere and cannot find why...