There aren't double postcards with the indication of "message" and "reply". As they were correctly separated, there are no forms to differentiate the message and reply postcard and the simple one. According to studies that I have performed, this difference may be seen when we consider – Single Postcard: a) the text (Neste lado só se escreve o endereço) it's 41 mm long, b) the distance of third line to the frame is of 9 or 10 mm and c) the broken icons position on the frame is according to the presented in fig 1 and 2. Double Postcard: a) the text (Neste lado só se escreve o endereço) is 40-41 mm long, b) the third line distance from the frame is 9 mm for the message and 10 mm for the reply and c) the broken icons position on the frame is according to the presented in figure 4, 5 and 6
The 20 reis postcard corresponds to the urban posting, this is inside the town. However if it was complemented with the necessary postage requirements, it could circulate aboard: National territory (between two cities): 40 reis (20 reis for the postcard and 20 reis more for the stamp) and International: 80 reis (20 reis for the postcard and 60 reis more for the stamp) (fig 5).
According to H. Ponge - June/1974, the re printing exists and it is characterized by the existence of a fourth elliptic line on the Coat of Arms. This matter must still be analyzed as the wearing of the "plate" may provoke the dismembering of the "lacy" that involves the arms, generating the 4th line characteristic of the reprinting noticed by Ponge. I do not have any study on the material sufficiently concrete.
There is an essay of the 20 reis postcard in wine color: the Coat of Arms in rectangular frame (Standard adopted for the 80 reis postcard). On the left low corner, under the frame, there is the indication of Essay. (fig 8)
The postcards of 20 reis were demonetized (simple and double) on April 1st 1889, by the publication of December 12th 1888.