Once upon a time, in the late '70's I started using Mobil 1 synthetic while stationed in Fairbanks, AK. The oil came in silver metal cans and stated the oil was good for 1 year/25,000 miles whichever came first. At 6 months or 12,250 miles replace oil filter and top off oil. IIRC, the OEM's didn't like that so Mobil eventually removed their change procedure and just said follow owner's manual.
I follow my DIC, sort of. Generally try to make the 1 year or 0% remaining but end up changing a little sooner because of up coming trips and don't want to hassle with an oil change on the road. Use Amsoil now, have used Rotella, Valvoline and Mobil 1 synthetics and in the 2 GM Duramax trucks no matter what I did, the % and mileage ended up with basically a 1 to 1 ratio.