  In our 2013 Astronomical Review article, we discussed the statistics of
variability for 633 faint spectral type A-F stars observed by the Kepler
spacecraft during Quarters 6-13. We found six stars that showed no variability
with amplitude 20 ppm or greater in the range 0.2 to 24.4 cycles/day, but whose
positions in the log g--Teff diagram place them in the delta Sct or gamma Dor
pulsation instability regions established from pre-Kepler ground-based
observations. Here we present results for 2137 additional stars observed during
Quarters 14-17, and find 34 stars that lie within the instability regions. In
Paper I, we included a +229 K offset to the Kepler Input Catalog Teff to take
into account an average systematic difference between the KIC values and the
Teff derived from SDSS color photometry for main-sequence F stars (Pinsonneault
et al. 2012). Here we compare the KIC Teff value and the Teff derived from
spectroscopy taken by the LAMOST instrument (Molenda-Zakowicz et al. 2013,
2014) for 54 stars common to both samples. We find no trend to support applying
the offset, but instead find that a small average temperature decrease relative
to the KIC Teff may be more appropriate for the stars in our spectral-type
range. If the offset is omitted, only 17 of our 34 `constant' stars fall within
the instability regions. For the two `constant' stars also observed by LAMOST,
the LAMOST Teff values are cooler than the KIC Teff by several hundred K, and
would move these stars out of the instability regions. It is possible that a
more accurate determination of their Teff and log g would move some of the
other `constant' stars out of the instability regions. However, if average
(random) errors in Teff are taken into account, 15 to 52 stars may still
persist within the instability regions. Explanations for these `constant'
stars, both theoretical and observational, remain to be investigated.
