Then I went to Google Earth map looking at the 2024 October 01th satellite photo at Yanliang Xian AVIC factory, and it became clear that the 15 Y20s there are
1. Ten Y20B, using the white spot as identification
2. Four YY20 using the shape of the rear end of sponson as identification, and also lack of the white spot.
3. One yellow skin YY20 also using shape of sponson as identification.
Therefore we can conclude that there are at least 10 Y20B, or if the five Y20B in Kaifeng are different aircraft from those spotted n Yanliang, then there are at least 15 Y20B as at now.