Just got my car back from it's 3rd variable service ,A3 2.0 TDI Sport ,38000 miles showing . Audi dealer has said it needs cam belt replaced (54 plate ) .i thought it was only changed at 60000 !. They said it is now 60000 or 5 years whatever comes first . when did they change it ? can't see any mention of 5 years in service handbook . Also why do they keep changing the type of oil they put in .Last service the put in mobil 1 now it's castrol Edge ?