Excursion of the evolutionary track of a 1.1 M_⊙ star of solar metallicity (left panel) and the variation of the surface carbon of the same 1.1 M_⊙ model star during the AGB phase. The red box on the left panel indicates the effective temperature and luminosity (with the corresponding error bars) given for ID 30 in Kamath et al. (2022), whereas the red vertical line in the right panel indicates the surface [C/Fe] of ID 30.