Evolutionary tracks for two systems starting mass transfer above the gap. The initial parameters are M_WD = 0.8 M_⊙, M₂ = 0.6 M_⊙, and P_orb = 0.25 (black) and 1.0 days (red). The horizontal gray line in the bottom panel corresponds to log(Tc) = 6.742366, which is the core temperature at the onset of crystallization. The vertical lines refer to the period minimum of P_min = 76 − 82 min, and the period gap (2.15 − 3.18 h). While the system represented by the red track detaches above the gap because the white dwarf crystallizes before mass transfer starts, CVs that start mass transfer with a noncrystallizing white dwarf detach after they have passed the period minimum (black track). We note that the period minimum is at shorter periods for systems that previously generated a white dwarf magnetic field. This is because magnetic braking is reduced as some of the open field lines of the donor star are affected by the white dwarf magnetic field.