Son lived in NY until he enlisted in Navy 8/7/14. Has been in IL, CT, GA and currently in WA where he'll be for about 4 years. Does he still pay NY state tax?

He is only in NY when he gets leave which is only about once a year.  His W2 has his total wages earned for 2016 in the "state tax" area.  Can he amend his W-2 or submit orders with it?