(written from a Production point of view)
The USS Jupp was a kitbash studio model built by the VFX house hired by Paramount Pictures for special effects in the episode DS9: "A Time to Stand". The Jupp was made with parts from the refit Constitution-class starship that bore a likeness to the Constellation-class; however, this ship possessed only a single ventral pylon and dual nacelle emplacement.
The art department would lend assistance during the construction phase. This starship was placed in the deep background and wasn't seen clearly in the episode. The first image of the USS Jupp appeared in the Star Trek: Deep Space Nine Technical Manual as a drawing. Later, images of the model appeared on the web and in the wbm. According to the Technical Manual, the Jupp participated in "Operation Return" featured in DS9: "Sacrifice of Angels".