According to a 1930 New York Times article, Wu Chung-chieh, a professor of the Chengdu University, discovered Imperial Chinese government records from 1827 congratulating Li Ching-Yuen on his 150th birthday, and further documents later congratulating him on his 200th birthday in 1877.
http://thenewyorkevening.us/2017/05/02/256-year-old-man-breaks-his-silence-before-dying-and-reveals-shocking-secrets-to-the-world/#
Toms Blog on Life and Livingness