Claiming a Dependent

Appears my son filed a tax return claiming a personal exemption; which means I am not able to claim him as a dependent.  He lived with me for 6 months of 2016 before leaving for the Navy (1/1/16 - 6/14/16 -approx).  He filed with Turbo Tax; is he able to change his return so that I am able to claim him for a portion of 2016?