Convectively mixed core mass for models with (black dots) and without overshooting (black stars) on the ZAMS. Blue and green ellipses show the same quantity, but using a geometrical cutoff for the overshooting and observational constraints by Mombarg et al. (2019), respectively. The red triangles denote the derived upper limits from our simulations. The black cross indicates the size of the mixed core of a 2.0 M_⊙ star close to the end of its main-sequence evolution when the model is computed without overshooting.