Is the Sole Survivor active duty or reserves?

[GestapoSantaClaus]

Seriously where is the dude stationed? Guys who are active duty in the military don’t exactly have the ability to live wherever they want. “Hey we really need to get this invasion of China moving but we’re still waiting for replies from our troops telling them to move back to the base”. I don’t think any thought was put into his line of work (though it really shouldn’t have because it should be left up to the player).

 

[Lone Cat]

According to Vault Tec Rep (as a human at the beginning of the game, not a ghoul who might be given a space (and social) in Sanctuary 210 years later) Nate (default name of MALE sole survivor, chosing him as a player will eliminate Nora and vice versa) is a Sino-American war veteran, the Intro (and also its 'War never changes' narrative) did feature him as an US Army Soldier (to be specific, 2nd Btn, 108th Inf. Rgt.) it is likely that he's among an active combat troopers (Line Infantrymen, Not sure about American doctrine of the alternate verse that what is the role of 'Infantry' regiment in the warfare... but his unit is not aerial depoyed one either) ) holding a laser rifle and wearing combat armor (rather than power armor... but he did get that training though). the Rep did grant Nate and Nora family a space in Vault 111 as a reward to his patriotic service to the United States (.. the Vault 111 itself is the place where Rep himself is expected to join but Garrisoning troops didn't let the Rep in.. nor did he gains any clearances to know whether did Vault Experiment did exists, otherwise he willl not become a ghoul (but won't survive Cryocell either )

http://fallout.wikia.com/wiki/Nate
To Answer the question. Nate was assigned to Active Duty.