Phase portraits on the (θ_z − θ_R, J_z) plane for orbits along the major axis of the bar with fixed H_J = −2.2. These are the same portraits contained in the red box in Fig. 3. Portraits are numerically obtained at three points in time (t = 160,  180,  200). The bold arrows show the possible and forbidden (for a given H_J) paths of transformation of vCIR+ orbits (two left panels) and vCIR+ with BAN orbits (right panel) during the evolution of the phase space.