They should be replaced when a visual inspection says they're cracking. My A/C belt started squeaking at 40K miles, but at 5 years or so. I replaced both.
Thank you
On my Honda and Lexus I replace the timing belt at 90k
I hadn't heard of a drive belt prior
My 2012 purchased new in 2011 turned 50k today. I plan to keep her till 100k or so at which point going to replace with a land cruiser