I know this is going to be controversial, as there are a lot of old school car people here. But I'll share it anyway.
When I bought my Outback, Subaru specifically recommended leaving the factory fill motor oil in for the full recommended oil change interval. Their explanation was twofold.
First, they explained that modern engine manufacturing and assembly processes are so much better than those of yesteryear, that engines assembled today are not at risk of having metal shavings and debris inside them. Second, they explained that there is benefit to leaving the factory fill in place for the full oci, so the additives could do all the good they are intended to.
I know that is a really hard concept for many. I couldn't do it either. I did the first oil change on my Outback at 900 miles, then changed the filter at 3700 miles before starting oil changes at the Subaru recommended interval.