  We study the mid-egress eclipse timing data gathered for the cataclysmic
binary HU Aquarii during the years 1993-2014. The (O-C) residuals were
previously attributed to a single ~7 Jupiter mass companion in ~5 au orbit or
to a stable 2-planet system with an unconstrained outermost orbit. We present
22 new observations gathered between June, 2011 and July, 2014 with four
instruments around the world. They reveal a systematic deviation of ~60 - 120
seconds from the older ephemeris. We re-analyse the whole set of the timing
data available. Our results provide an erratum to the previous HU Aqr planetary
models, indicating that the hypothesis for a third and fourth body in this
system is uncertain. The dynamical stability criterion and a particular
geometry of orbits rule out coplanar 2-planet configurations. A putative HU Aqr
planetary system may be more complex, e.g., highly non-coplanar. Indeed, we
found examples of 3-planet configurations with the middle planet in a
retrograde orbit, which are stable for at least 1Gyr, and consistent with the
observations. The (O-C) may be also driven by oscillations of the gravitational
quadrupole moment of the secondary, as predicted by the Lanza et al.
modification of the Applegate mechanism. Further systematic, long-term
monitoring of HU Aqr is required to interpret the (O-C) residuals.
