Schematic representation of the satellite orbits for Selene (left) and Oceanus (right). On the y-axis we plot the three-dimensional distance (R_3D) from the satellite centre to the host galaxy centre. On the x-axis we plot the lookback time (13.5 Gyr being the beginning of the simulation). Each point represents one satellite at a given snapshot with points corresponding to the same satellite at different timesteps linked by a solid black line. In some cases, the halo tracking between snapshots fails, leading to missing connecting lines. We colour-code the points according to log₁₀(M_sat/M_host) (the size of each point is also proportional to that value) as an indicator of the magnitude of the mergers. We have applied a cut in log₁₀(M_sat/M_host) to clean the plot of the least massive satellites; satellites with (M_sat/M_host)_t below 0.005 are ruled out in the plots. The dashed red line represents the time evolution of the host galaxy virial radius. Last merger times (t_jump) are denoted via dashed cyan vertical lines. For Selene (left) the last merger happened 6.0 Gyr ago with M_sat/M_host ~ 0.089 when it enters the virial radius and ~0.0126 when the merger happens. The two merging events associated with the cessation of the two assembly phases in Oceanus (right), where (M_sat/M_host)_v is ~0.056 (0.05) and (M_sat/M_host)_t is ~0.006 (0.005) for the first (second) merging event finishing each epoch.