Upper panel: snapshot of gas density of a single jet (model M1) at t = 1875 yr. One can see the work-surface structure due to the consideration of the variable jet. The envelope shows a higher density at the “base” of the jet and a lower one toward the front. Lower panels: snapshots of gas density of the jet-interaction model (model M2) at three evolutionary times: t=1375, 1625, and 1875 yr (top, middle, and bottom panels). Considering the estimated age of the Cep E protostellar outflow of ∼1500 yr (de A. Schutzer et al. 2022), different stages of evolution around this age are shown. All the snapshots are present on the xy-plane.