  Recently, Bailey et al. (2015) made a direct measurement of the Iron opacity
at the physical conditions of the solar tachocline. They found that the
wavelength-integrated Iron opacity is roughly 75% higher that what the OP and
OPAL models predict. Here, we compute new opacity tables with enhanced Iron and
Nickel contributions to the Rosseland mean opacity by 75% each, and compute
three dense MESA grids of evolutionary models for Galactic O- and B-type stars
covering from 2.5 to 25 M$_\odot$ from ZAMS until $T_{\rm eff}=10\,000$ K after
the core hydrogen exhaustion. We carry out non-adiabatic mode stability
analysis with GYRE, and update the extension of the instability strips of
heat-driven p- and g-mode pulsators, and the hybrid pulsating SPB - $\beta$ Cep
stars. We compare the position of two confirmed late O-type $\beta$ Cep and
eight confirmed hybrid B-type pulsators with the new instability domains, and
justify that $\sim$75% enhancement, only in Iron opacity, is sufficient to
consistently reproduce the observed position of these stars on the $\log T_{\rm
eff}$ versus $\log g$ plane. We propose that this improvement in opacities be
incorporated in the input physics of new stellar models.
  To reproduce the results, all software, opacity tables and the new
instability strips are freely available for download at the following URL:
https://fys.kuleuven.be/ster/Projects/ASAMBA.
