Note in the "Standard Catalogue of China & Treaty Ports", 1935:
Tientsin
Quote:
An important city and port of Tientsin with a large population and a strong foreign community could undoubtly have special stamps as other Treaty Ports but this question has never been considered by the Municipality of that town.
According to the Hong-Kong Philatelist of June 1893, stamps with above design, with or without overprint "Postage Due" have been made privately in order to defraud collectors.
The Tientsin stamps mimicked the first issues of the empire issues of 1878, while the overprint mimics the postage due overprint on the Wuhu issues of 1895.