Minimum time spans in a fully liberal era a) for several mass loss rates when the mass ratio is fixed at q = 0.5 and b) for various mass ratios when the mass loss rate is fixed at −10^-8 M_⊙ yr^-1. Computations were performed considering that the transferred material is lost from the system through a hot-spot emission, located either on the less massive (squares) or the more massive component (circles), and via the L2 (up triangles) or the L3 point (down triangles), for noise levels equal to 0.001 d (left vertical axis) and 0.03 d (right vertical axis). The dashed line in the right panel covers the range within which the critical value q_cr ≈ 0.72 lies. (This figure is available in color in the electronic edition.)