Fr Sergiy was the first rector of the St Innokenty Mission Church in Tianjin. He was the son of the Hieromartyr Mitrophan according to page 28 of Aug-Sep 1947 issue of "Kitajskij Blagovestnik".
(Aug-Sep 1947 issue,
pg 22, in Russian)
interior view of St Innokenty Mission Church
with Fr Sergiy Chang
1948 photo from Museum of Church Archaeology, MDPA