  We investigate the early onset of pionic color transparency ($\pi$CT)
observed at Jefferson Laboratory (JLAB) in semi--exclusive pion
electroproduction reaction $A(e,e'\pi^+)$ off nuclei. In the present
description the primary $\gamma^*p \to \pi^+ n$ interaction is described very
well both for the longitudinal and the transverse polarizations. For the final
state interactions a coupled--channel treatment of the interactions of
transmitted hadrons allows to go beyond the Glauber approximation. We show that
a proper distinction between the soft hadronic and hard partonic components of
the electroproduction amplitude is essential for a quantitative description of
the measured nuclear transparency. The data are well reproduced if one assumes
that point--like configurations are produced in the regime of hard
deep--inelastic scattering (DIS) off partons and dominate the transverse
channel.
