When did the center of calligraphy activities gradually shift from Beijing to Suzhou in the south of the Yangtze River?

In the middle of Ming Dynasty, with the rise of Wumen Calligraphy School, the calligraphy circle of Ming Dynasty, which was bound by the calligraphy style of Yuan people for a hundred years, gradually entered the best state, thus opening a quite wonderful scene in the history of calligraphy in China. At this time, the calligraphy activity center has gradually moved from Beijing to Suzhou in the south of the Yangtze River.