Spatial and photometric information of the spectroscopic targets. Left panel: spatial distribution of the three fields observed with FLAMES (red, green, and blue circles for FLD-121, FLD-339, and FLD-419, respectively) superimposed on the map of the SMC RGB stars with G between 16 and 19 from Gaia EDR3 (Gaia Collaboration 2021), revealing the old spheroid of the SMC. The white plus indicates the position of the SMC centre derived by Ripepi et al. (2017). Right panel: Gaia EDR3 CMDs of the three SMC fields (grey points, Gaia Collaboration 2021). The spectroscopic GIRAFFE targets are superposed (same colours as in the left panel). The main sequence of MW GC 47 Tucanae is clearly visible in the CMD of FLD-121.