Very interesting things happened due to the need to expand the military for WW 2. My dad was part of a unit of technicians drafted for their civilian skills. 4 weeks of "basic" and he was a Corporal. (Seen his pay book.) He was a Canadian citizen not naturalized when his parents were as he was over 18 by then. He was given the paperwork and ordered to become a citizen because at that time they would not reply a non-citizen. Took about 3 weeks. Decisions were made and implemented as if they mattered!
A lot of senior NCOs were directly commissioned as Captains; his First Sgt. was, and hit O-6 before the end of the war.