  We present ASCA data on RE J2248-511, extending existing optical and soft
X-ray coverage to 10 keV, and monitoring the soft component. These data show
that, despite a very strong ultrasoft X-ray excess below 0.3 keV and a soft
0.3--2 keV spectral index in earlier ROSAT data, the hard X-ray spectrum
(alpha~ -0.8; 0.6-10 keV) is typical of type 1 AGN, and the soft component has
since disappeared. Optical data taken at two different epochs show that the big
blue bump is also highly variable. The strength of the ultrasoft X-ray
component and the extreme variability in RE J2248-511 are reminiscent of the
behaviour observed in many narrow line Seyfert 1s (NLS1s). However, the high
energy end of the ROSAT spectrum, the ASCA spectrum and the Balmer line full
widths at half maximum of ~3000 km/s in RE J2248-511, are typical of normal
Seyfert 1 AGN.
  The change in the soft X-ray spectrum as observed in the ROSAT and ASCA data
is consistent with the behaviour of Galactic Black Hole Candidates (GBHCs) as
they move from a high to a low state, ie. a fall in the ultrasoft component and
a hardening of the X-ray continuum. This GBHC analogy has also been proposed
for NLS1s. Alternatively, the variability may be caused by opacity changes in a
hot, optically-thin corona which surrounds a cold, dense accretion disc; this
was first suggested by Guainazzi et al. for 1H0419-577, an object which shows
remarkably similar properties to RE J2248-511.
