Estimated Galactocentric birth radii, 〈R_b〉, in contrast to the present guiding radii, 〈R_g〉. Both radii are measured in kiloparsecs and encompass all stars in our sample that are part of the disc, according to Fig. 7. Each distinct subplot delineates a specific star group, classified using hierarchical clustering (as illustrated in Fig. 1). The subplots are arranged in descending order of the median iron abundance, 〈[Fe/H]〉. At the upper part of each subplot, 〈[Fe/H]〉 and ${\overline{t}}_{\star }$ are displayed. Furthermore, the overall standard deviations (σ) for 〈R_b〉 and 〈R_g〉 are exhibited at the lower right corner of each subplot. We overlay the 2D-Gaussian kernel densities to illustrate the concentration patterns of the stars in each subplot. A reference black dashed line is incorporated, signifying the point of parity between both radii (〈R_b〉 = 〈R_g〉). The colour scheme remains consistent with the preceding figures.