  The phenomenological torque balance model previously introduced to describe
the electrically assisted light-induced gliding is generalized to study the
reorientation dynamics of the nematic liquid crystal easy axis at photoaligned
azo-dye films under the combined action of in-plane electric field and
reorienting UV light linearly polarized at varying polarization azimuth,
$\varphi_p$. We systematically examine the general properties of the torque
balance model by performing analysis of the bifurcations of equilibria at
different values of the polarization azimuth and apply the model to interpret
the experimental results. In our experiments, it is found that, in contrast to
the case where $\varphi_p=0$ and the light polarization vector is parallel to
the initial easy axis, at $\varphi_p\ne 0$, the pronounced purely photoinduced
reorientation occurs outside the interelectrode gaps. It is also observed that,
in the regions between electrodes with non-zero electric field, the dynamics of
reorientation slows down with $\varphi_p$ and the sense of easy axis rotation
is independent of the sign of $\varphi_p$.
