There's been much debate about this.
I called vw, it's 4 years for the belt change.
I've had reports from stealers, indies and Vw that all contradict each other.
Lowest being stealer 40k highest VW stating 120,000!!! This was via the 0800 number at customer services and the girl put me on hold whilst she spoke to the correct technical dept.
I just done mine at 3.5 years and 36k as in September at 4 years I reckon I would have the money. So it's done and peace of mind prevails.