There are a great deal of good answers here. The technology in todays oil is far better than years ago. We have an LB7 Duramax engine and the recommended oil change interval is 10,000 miles. I have never gone that long on an oil change. I usually change the oil every 5,000 miles, even on the road. I can't see any long term damage to your engine if this is the only time you go over your comfort zone on one oil change. It has been recommended, and I agree, to check your oil level often and enjoy your trip.