FYI, I had to pick some of my shiranui/sumo fruits since my 2020 grafted branches were to small to hold the weight of these.
Here's a few photos of the sumo picked to early. The 3 sumo fruits were picked this week because my grafted branches couldn't hold the weight of these fruits. The sumo had no sweet taste, more tart than anything but I ate one. Very surprised to find 3 seeds in the one sumo that I cut up. Last year I did not find any seeds in 20 sumo fruits from my tree. I do notice that even though my budwood grafts are from UCR, CCPP orders, there seems to be two slightly different shiranui varieties. The one's I grafted in 2017 has the nice bump on the neck and it doesn't start to turn color until end of Nov and ripens by Feb. The newer grafts from 2020 do not have much of a neck as you can see in the photo, fruits are more flat, and they start turning color in Oct. I will wait until end of Dec-Jan to taste these again, hope these 2020 grafts get sweet. Also of note is that the 2017 grafted branches still have small green fruits, not full size yet. Maybe as Millet says, there are variation in the fruits. Maybe when the new grafts from 2020 gets older (2-3 yrs) the fruit coloring will follow the older 2017 grafted branches and taste will improve. If not, I will just cut off the new grafts and use my branches from 2017 on these trees.