And diesels require more frequent oil changes than gasoline engines!
I gather you are from Canada? As I understand it, performing your own maintenance can void your warranty. Very consumer unfriendly, and a prop to dealers performing unrealistically frequent services. I am not familiar with Canadian legal principles but it would seem to me performing your own service in an unrelated area such as changing oil would not void the warranty on say your radiator. It certainly does not in the US no matter who performs the service.
My own plans are to let Kia do the complementary first service at 8,000 miles this coming Monday with full synthetic O-20 oil, and do my own after that with probably 20,000 mile intervals with the best oil and filters (non-paper ones). I'm going to cut open the OEM filter that is removed on Monday to determine construction. If paper, I will replace just the filter at 16,000 miles.
2018 Kia LX HEV Metal Stream with Advanced Tech