Comparison of our observed CNO-abundances to the theory of CNO processing. Only for three sources all abundances were measured (red triangles), for the rest the oxygen abundance is fixed to the LMC baseline value of n_O = 8.35 (see text). The yellow shaded region marks the regime between the analytical limiting solutions (CNO- and CN-equilibrium) of Maeder et al. (2014), their Eqs. (14) and (17), respectively. Dotted, dashed and solid blue lines show evolutionary tracks of 30, 60 and 150 M_⊙, respectively (Brott et al. 2011a; Köhler et al. 2015), where light and dark blues indicate models with low (~100 km s⁻¹) and high (~500 km s⁻¹) initial rotation velocities.