  In this work, we self-consistently explore the possibility of charged pion
superfluidity and cosmic trajectories in early Universe under the framework of
Polyakov-Nambu--Jona-Lasinio model. By taking the badly constrained lepton
flavor asymmetries $l_{\rm e}$ and $l_\mu$ as free parameters, the upper
boundaries of pion superfluidity phase are consistently found to be around the
pseudocritical temperature at zero chemical potentials. So the results greatly
support the choice of $T=0.16~{\rm GeV}$ as the upper boundary of pion
superfluidity in the previous lattice QCD study. Take $l_{\rm e}+l_\mu=-0.2$ as
an example, we demonstrate the features of pion condensation and the associated
cosmic trajectories with the evolution of early Universe. While the trajectory
of electric chemical potential reacts strongly at both the lower and upper
boundaries of reentrant pion superfluidity, the trajectories of other chemical
potentials only respond strongly at the upper boundary.
