Overview of our binary evolution models with an initial primary mass of 12.6 M_⊙. Each pixel represents one detailed binary evolution sequence, with colors indicating the status of the primary star in the midpoint of core helium burning (when central helium mass fraction is Y_c = 0.5). At this point, the secondary is a core hydrogen burning star. Black lines delineate the boundaries between different mass transfer cases, while the black-hatched region highlights models that will undergo another phase of mass transfer after primary’s core helium depletion (“Late MT”). Models that are expected to merge and models that did not converge due to unknown error are also indicated.