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In our 2013 Astronomical Review article, we discussed the statistics ofvariability for 633 faint spectral type A-F stars observed by the Keplerspacecraft during Quarters 6-13. We found six stars that showed no variabilitywith amplitude 20 ppm or greater in the range 0.2 to 24.4 cycles/day, but whosepositions in the log g--Teff diagram place them in the delta Sct or gamma Dorpulsation instability regions established from pre-Kepler ground-basedobservations. Here we present results for 2137 additional stars observed duringQuarters 14-17, and find 34 stars that lie within the instability regions. InPaper I, we included a +229 K offset to the Kepler Input Catalog Teff to takeinto account an average systematic difference between the KIC values and theTeff derived from SDSS color photometry for main-sequence F stars (Pinsonneaultet al. 2012). Here we compare the KIC Teff value and the Teff derived fromspectroscopy taken by the LAMOST instrument (Molenda-Zakowicz et al. 2013,2014) for 54 stars common to both samples. We find no trend to support applyingthe offset, but instead find that a small average temperature decrease relativeto the KIC Teff may be more appropriate for the stars in our spectral-typerange. If the offset is omitted, only 17 of our 34 `constant' stars fall withinthe 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, andwould move these stars out of the instability regions. It is possible that amore accurate determination of their Teff and log g would move some of theother `constant' stars out of the instability regions. However, if average(random) errors in Teff are taken into account, 15 to 52 stars may stillpersist within the instability regions. Explanations for these `constant'stars, both theoretical and observational, remain to be investigated.

The Occurrence of Non-Pulsating Stars in the gamma Dor and delta Sct Pulsation Instability Regions: Results from Kepler Quarter 14-17 Data