GM programmed the OLM to hit 0% (plus some safety margin) with a basic oil meeting the Dexos spec (the lowest common denominator, if you will). It's pretty sophisticated technology, and has far more inputs than changing based on mileage alone. Your car is assuming that you're using a 5w30 meeting Dexos spec (synthetic or a robust blend) and its calculations are pretty good with that assumption. Is Redline better oil than what they programmed it for? Sure. But it's difficult to quantify by how much. And there's also the question of contamination vs breakdown (ostensibly, better oil will resist breakdown for longer (thanks to some combination of more additives and a more robust base oil) but will still be susceptible to being contaminated with fuel, moisture, etc.)
Your being on track for a bit over 3000 miles puts you at less than half the optimal mileage case as per GM, meaning that you really must be short-tripping it pretty hard or something (7500 miles has been the "ideal conditions" maximum mileage with GMs for a while now) - you're losing 1% per 30-35 miles or so, on average, and in ideal conditions you'd lose 1% per 75 miles or so.
