cambelt change on peugeot 407 2004?

Hi, when do you have to change a cambelt on a peugeut 407 2004? I've been told 160k or 8 yrs and also 80k or 7yrs, 2 different dealers...also, does the car do anything to show it needs that work? I dont do a lot of mileage..can it wait a little longer to be change?
Thanks