The curtain remains open: NGC 2617 continues in a high state
  Optical and near-infrared photometry, optical spectroscopy, and soft X-ray
and UV monitoring of the changing look active galactic nucleus NGC 2617 show
that it continues to have the appearance of a type-1 Seyfert galaxy. An optical
light curve for 2010-2016 indicates that the change of type probably occurred
between 2010 October and 2012 February and was not related to the brightening
in 2013. In 2016 NGC 2617 brightened again to a level of activity close to that
in 2013 April. We find variations in all passbands and in both the intensities
and profiles of the broad Balmer lines. A new displaced emission peak has
appeared in H$\beta$. X-ray variations are well correlated with UV-optical
variability and possibly lead by $\sim$ 2-3 d. The $K$ band lags the $J$ band
by about 21.5 $\pm$ 2.5 d. and lags the combined $B+J$ filters by $\sim$ 25 d.
$J$ lags $B$ by about 3 d. This could be because $J$-band variability arises
from the outer part of the accretion disc, while $K$-band variability comes
from thermal re-emission by dust. We propose that spectral-type changes are a
result of increasing central luminosity causing sublimation of the innermost
dust in the hollow biconical outflow. We briefly discuss various other possible
reasons that might explain the dramatic changes in NGC 2617.
