I have always drained at 500 miles for the first change then go out to about 1500 for the second. After that I usually run most synthetics to 5-6K with a premium filter and call it good.
Doug Hillary is your man on this topic. He has a lot of experience with this in many engines. Hopefully he will chime in. His advice will be more scientific if you will, while the majority of bitog will give you more anecdotal advice. Im by no means knocking the non scientific opinions as what I have recommended above is by no means proven with data. It just makes me feel good and has always worked.