Location of the selected sample of H-rich stars (213 objects in total) in both the HR (upper panel) and Kiel (lower panel) diagrams. Light blue points symbols show the location of the subsample for which interpolation in both diagrams indicate a consistent age and mass (88 objects, see text). Grey continuous lines show the location of interpolated tracks for different masses (0.5, 0.55, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, 0.95, 1, 1.1, 1.2, 1.3 M_⊙, and Z₀ = 0.01, from right to left). Brown and red lines show isochroned in the post-AGB evolution. The doted grey line indicates a typical post-EHB evolution.