Dipole (ℓ = 1, upper panel) and quadrupole (ℓ = 2, lower panel) average of the computed period spacings, , assessed in a range of periods that includes the periods observed in EC 20058, shown as curves of different colors according to the different stellar masses. We consider the effective temperature T_eff = 25 500 ± 500 K (Koester et al. 2014), and the possible period spacing values ΔΠ = 12.78, 15.84, 23.90, 26.36, 41.11, 47.67 s (see Fig. 16). For a discussion, see the text.