If you are fine using Purolator Classic, I don't see any reason to change it out earlier than your oil change. I also don't recommend that you look to Purolator to determine change frequency. Their current recommendation for PureOne filters is 3,000 miles, 3 months, or Manufacturer's recommendation. In a well running vehicle with a tight air system, most any filter can actually handle 8,000 miles as well as 3,000 miles. Most filters will filter better with some use than when new. Clogging filters and heat damaged filters need to be replaced of course.
Quote: "Purolator PureONE oil filters should be replaced every 3,000 miles or 3 months depending on the driving conditions - or unless otherwise specified by the vehicle's manufacturer."
http://www.purolatorautofilters.net/products/oil_filters/Pages/pureoneoilfilters.aspx
Quote: "Purolator PureONE oil filters should be replaced every 3,000 miles or 3 months depending on the driving conditions - or unless otherwise specified by the vehicle's manufacturer."
http://www.purolatorautofilters.net/products/oil_filters/Pages/pureoneoilfilters.aspx