It doesn’t really bother me either way synthetic or regular. I think engine wear is direct result of the crud in your oil. And to that I don’t think it matters regular or synthetic. It’s pretty clear that synthetic lasts (maintains the properties of the spec) longer so it probably lubricated better too, but that doesn’t change the issue of engine wear and the crud in the oil. Are you changing the oil because it is dirty, or because it has losts it lubricating properties? I typically follow the spec of the manufacturer and be done with it. Seems like they have done way more testing on the longevity of their engines than I could second guess. Change it close to the schedule and put the drain plug in before refilling.