I was at 7 months with this oil, and the manual calls for 6 months OCIs, so I went ahead and changed it. I didn't have any concerns, but I did want to get a before number on the silicone before I replace the factory air filter. I'll test the oil again after a full OCI with the new air filter. The manual says to change at 30k miles, but I am probably going to do it this Spring at 45k. I had a Fram XG3614 filter on it.