Maximum Eddington factor in the analysed stellar models as a function of T_eff for all stellar models shown in Fig. 2, i.e. with Γ_max> 0.9. The three peaks in Γ_max at T_eff/ kK of ~55, 25, and 5.5 correspond to the three opacity bumps associated with the ionisation zones of Fe, HeII and H respectively. Inset: models with Γ_max> 0.94 and T_eff/ kK ≳ 10 kK. The blue horizontal line at Γ_max = 1 is drawn for reference.