  We report on a numerical study of the Boltzmann equation including
$2\leftrightarrow 2$ scatterings of gluons and quarks in an overoccupied Glasma
undergoing longitudinal expansion. We find that when a cascade of gluon number
to the infrared occurs, corresponding to an infrared enhancement analogous to a
transient Bose-Einstein condensate, gluon distributions qualitatively reproduce
the results of classical-statistical simulations for the expanding Glasma.
These include key features of the distributions that are not anticipated in the
"bottom-up" thermalization scenario. We also find that quark distributions,
like those of gluons, satisfy self-similar scaling distributions in the
overoccupied Glasma. We discuss the implications of these results for a deeper
understanding of the self-similarity and universality of parton distributions
in the Glasma.
