HR diagram showing the trajectories and the intervals where the Huntsman states occur (blue). The first initial period that allows the mass transfer (the so-called case B) is clearly seen on the bottom, producing the ample and slanted “V” track is P_orb, i = 1 d, while all shorter periods end in downward tracks. It is important to remind the reader that this is somewhat sensitive to the treatment of the physics and small variations may occur for different choices of the braking and other features (see, e.g., Istrate et al. 2014; Misra et al. 2025b).