Orbital period versus companion mass for diverging binary tracks from our simulated grids that have a similar NS spin as the observed PSR J0952–0607 (1.41 ms) within a 10% margin (dashed gray curves). The term M_c is the mass of the companion to the NS, and P_orb is the orbital period. All the tracks shown have β = 0.3 and f_pulsar = 0.5. We further show the binary that best matches the sources in its orbital evolution in blue curve, which has initial companion mass of 2.0 M_⊙, initial NS mass of 1.3 M_⊙, and initial orbital period of 1.0 d.