  We investigate the robustness of parity- and time-reversal ($\mP\mT$)
symmetric phase in an $N$-site lattice with position-dependent,
parity-symmetric hopping function and a pair of imaginary, $\mP\mT$-symmetric
impurities. We find that the "fragile" $\mP\mT$-symmetric phase in these
lattices is stronger than its counterpart in a lattice with constant hopping.
With an open system in mind, we explore the degrees of broken $\mP\mT$-symmetry
and their signatures in single-particle wavepacket evolution. We predict that
when the $\mP\mT$-symmetric impurities are closest to each other, the time
evolution of a wavepacket in an even-$N$ lattice is remarkably different from
that in an odd-$N$ lattice. Our results suggest that $\mP\mT$-symmetry breaking
in such lattices is accompanied by rich, hitherto unanticipated, phenomena.
