Expected runaway velocities (v_rem) of the surviving donor star plotted over the mass of the survivor (M_rem). Color indicates the time since the end of the most recent CE phase. The solid black line and red shading indicate the observed velocity and associated error bars of the hypervelocity hot subdwarf US 708 (Geier et al. 2015). The dashed black line and green areas indicates the galactic escape velocity (Piffl et al. 2014), including error bars; M_acc is the mass of the accreting WD at helium ignition.