exodus will provide him an opportunity to come home. he'll be charged leave so he might end up going in the hole and not be able to take much leave after AIT but at least he'll be home for Christmas.
As for leaving earlier..highly doubt it. We're busting at the seams right now.
Important: he'll have to provide his own tickets to/from and provide those to his drill sgt. the army doesn't pay your personal travel expenses.