Hiya,
Well I spoke to Virgin again, and they said that the call divert for busy calls had never been swiched on! So I guess you were right.
Codes still not working though... so currently I have calls that divert when busy or answered (Virgin set this up when I was on the phone, including the number to divert to), but no codes to give me the option to switch these services off or divert to a different number.
Could be worse but I would like to not be permanently rushing for the phone in case it diverts before I get to it.
Thanks for the help, but I am becoming more and more suspicious that codes on this old ntl line just do not exist.
Sian