First, you might compare this with our entry 20325409, which was in effect Part One of this series from 2020.  This latest version was issued on 19 May 2021, and bears the exact title:  “Maximum Cards of Ancient Chinese Paintings Postage Stamps: ‘Syzygy of the Sun, Moon, and the Five Planets’ by Xu Yang, Qing Dynasty (II)”.  Our scan shows the cardboard cover and two of the six cards in the set.  Grade: 1