VW polo cam belt change interval

According to Volkswagen UK, the belt ought to be changed at 5 year intervals on a vehicle built from Model Year 2010 (VW model years run from September). Here is the link to Volkswagen UK's specific advice. They state:

We recommend a cambelt change interval at 4 years for cars registered before September 2009, 5 years thereafter. Customers who reach the recommended mileage limited on their vehicles cambelts before 4 or 5 years maybe advised to change their cambelt sooner.

My 9 year-old Polo has been garage serviced since new. Nowhere on the service manual does it mention a timing belt change, but they look ok (not the polished tooth-lines of a well used belt, and makers marks still visible) According to auto trader, its 82,000 miles is above average for its age! So do I assume that around 9,000 miles a year is average? It means either 5years or approx 45,000 miles is the service interval! I've had an Audi A4 TDi belt fail catastrophically at 179,500, having had the previous main dealer belt change at 119,000 on a 60,000 mile regime.So no, I'm not taking any risks!