When should I change my Vauxhall Vectra's timing belt?

Having been caught out on my last Vauxhall with an expensive timing chain failure, when should I consider changing it on my 57-reg Vectra Estate Auto 1.9D (150) please? It's currently on 60,000 miles.
It's a belt, and the answer is NOW. And the tensioner. And the water pump, which has a nasty habit of seizing and throwing the belt off.
Answered by Honest John on

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