Plasma vertical velocity (v_y) for the simulated cases, comparing a successful CME (C1, left), eroded CME (C2, middle), and collapsed CME (C2_T⁻, right). Upper panels: Snapshots taken at a fixed time (t = 19 min). Bottom panels: Instances that maximise the contrast in the integrated bulk velocity of the MFR for each case (C1: t = 50 min, C2: t = 75 min, and C2_T⁻: t = 25 min; see Fig. 5). In all panels, the heliospheric current sheet formed along the x = 0 position is visible at heights above y = 2 R_⊙.