Hello, similar for me!
Personally my AN650 belt is 31500 km (20 000 Mi) old and does not present symptoms of ageing tire.
Today in France, nobody never replaced his.
A few times ago (3 months, 17000 Mi) after having rolled 3 hours under a tornado of rain, the belt emitted an enormous noise of foghorn. But since, all is again normal. (Water introduces by the grid of air filter of the CVT ... Breton rain - (weather french brittany
For information, I changed the belt of X9-500 Piaggio every 12 000 km (7 500 Mi).
not anxious? ...
sorry my english