Nice report! I will be sampling my 2014 with the same engine running M1 5/30. My ODO is about the same as yours. The sample will have about 10,000 miles on the interval so it will be good to compare the results.
It is what I would expect when using an extended performance oil and filter. I would stick with the 15,000 mile interval and no need to keep paying Blackstone labs to tell you what you now already know.