  We report a systematic NMR study on
[Sr$_4$Sc$_2$O$_6$]Fe$_2$(As$_{1-x}$P$_x$)$_2$, for which the local lattice
parameters of the iron-pnictogen (Fe$Pn$) layer are similar to those of the
series LaFe(As$_{1-x'}$P$_{x'}$)O, which exhibit two segregated
antiferromagnetic (AFM) order phases, AFM1 at $x'$=0-0.2 and AFM2 at
$x'$=0.4-0.7. Our results revealed that the parent AFM1 phase at $x$=0
disappears at $x$=0.3-0.4, corresponding to a pnictogen height ($h_{pn}$) from
the Fe-plane of 1.3-1.32 \AA, which is similar to that of
LaFe(As$_{1-x'}$P$_{x'}$)O and various parent Fe-pnictides. By contrast, the
AFM2 order reported for LaFe(As$_{0.4}$P$_{0.6}$)O does not appear at
$x\sim$0.8, although the local lattice parameters of the Fe$Pn$ layer and the
microscopic electronic states are quite similar. Despite the absence of the
{\it static} AFM2 order, reemergent {\it dynamical} AFM spin fluctuations were
observed at approximately $x\sim$0.8, which can be attributed to the
instability of the AFM2 phase. We suggest this re-enhancement of AFM spin
fluctuations to play a significant role in enhancing the $T_c$ to 17 K for
$x$=0.8-1. Finally, we discuss the universality and diversity of the
complicated magnetic ground states from a microscopic point of view, including
the difference in the origins of the AFM1 and AFM2 phases, and their relations
with the high superconducting transitions in Fe-pnictides.
