  Some observations and numerical simulations of disc-magnetosphere interaction
show that accretion can proceed in the propeller regime. When the Alfv\'en
radius is beyond the corotation radius, matter climbs up to the high latitudes
where the Alfv\'en surface is inside the equilibrium surface and can accrete.
We calculate the fraction of the mass flux in the disc that can accrete onto
the neutron star depending on the fastness parameter and the inclination angle
between rotation and magnetic axis. We find that, for a narrow range of the
fastness parameter, the Alfv\'en and the equilibrium surfaces intersect at two
different critical latitudes. While the system is transiting from the propeller
to the accretion regime (the initial rise of an outburst), the disc is already
thick and the part of the disc between these two critical latitudes cannot
accrete. In transitions from the accretion to the propeller regime (decay of an
outburst), the disc is thin, hence, full accretion of matter proceeds until the
Alfv\'en radius moves beyond the equilibrium radius at the disc-midplane.
Therefore, the accretion regime commences at a smaller fastness parameter than
it ceases. As a result, the transition from the propeller to the accretion
regime occurs at a luminosity higher than the transition from the accretion to
the propeller regime. We discuss the implications of our results for spectral
transitions exhibited by low-mass X-ray binaries.
