  The disc instability model accounts well for most of the observed properties
of dwarf novae and soft X-ray transients, but the rebrightenings, reflares, and
echoes occurring at the end of outbursts or shortly after in WZ Sge stars or
soft X-ray transients have not yet been convincingly explained by any model. We
determine the additional ingredients that must be added to the DIM to account
for the observed rebrightenings. We analyse in detail a recently discovered
system, TCP J21040470+4631129, which has shown very peculiar rebrightenings,
model its light curve using our numerical code including mass transfer
variations from the secondary, inner-disc truncation, disc irradiation by a hot
white dwarf and, in some cases, the mass-transfer stream over(under)flow. We
show that the luminosity in quiescence is dominated by a hot white dwarf that
cools down on time scales of months. The mass transfer rate from the secondary
has to increase by several orders of magnitudes during the initial
superoutburst for a reason that remains elusive, slowly returning to its
secular average, causing the observed succession of outbursts with increasing
quiescence durations, until the disc can be steady, cold, and neutral; its
inner parts being truncated either by the white dwarf magnetic field or by
evaporation. The very short, quiescence phases between reflares are reproduced
when the mass-transfer stream overflows the disc. Using similar additions to
the DIM, we have also produced light curves close to those observed in two WZ
Sge stars, the prototype and EG Cnc. Our model successfully explains the
reflares observed in WZ Sge systems. It requires, however, the inner disc
truncation in dwarf novae to be due not (only) to the white dwarf magnetic
field but, as in X-ray binaries, rather to evaporation of the inner disc. A
similar model could also explain reflares observed in soft X-ray transients.
