Outcome of the two-step interpolation scheme with supervised ML. Stellar tracks in the HR (top left) and Kiel diagram (top right) for unseen test initial masses are predicted as function of age τ. For comparison with the true test HR and Kiel tracks, see Fig. 4. For better visibility, the best- (bottom left) and worst-fit (bottom right) of tracks in the HR diagram, as assessed by the L2 measurement, are displayed separately.