  Measurements of disappearance channel of long baseline accelerator based
experiments (like NO$\nu$A) are inflicted with the problem of octant
degeneracy. In these experiments, the mass hierarchy (MH) sensitivity depends
upon the value of CP-violating phase $\delta_{CP}$. Moreover, MH of light
neutrino masses is still not fixed. Also, the flavour structure of fermions is
yet not fully understood. We discuss all these issues, in a highly predictive,
low-scale inverse seesaw (ISS) model within the framework of $A_4$ flavour
symmetry. Recent global analysis has shown a preference for normal hierarchy
and higher octant of $\theta_{23}$, and hence we discuss our results with
reference to these, and find that the vacuum alignment of $A_4$ triplet flavon
(1,-1,-1) favours these results. Finally, we check if our very precise
prediction on $m_{ee}$ and the lightest neutrino mass falls within the range of
sensitivities of the neutrinoless double beta decay ($0\nu\beta\beta$)
experiments. We note that when octant of $\theta_{23}$ and MH is fixed by more
precise measurements of future experiments, then through our results, it would
be possible to precisely identify the favourable vacuum alignment corresponding
to the $A_{4}$ triplet field as predicted in our model.
