Yeah, the Aviation Cadet guys are recruted as Enlisted for two years from the High School graduates (maximum age is 21 years old for the JASDF, 23 for the JMSDF). When they were promoted to the NCO (approximately one and one third years for JMSDF from 2017 and two years for JASDF), they were appointed as the "Aviation Officer Candidate", so they can finally start their flight training to achieve the PPL, CPL or whatever license to become an Naval Aviator/Flight Officer (Tactical Coordiantor) or Air Self Defence Force Pilot. As one kind of Officer Candidate, they are admitted to enter the wardroom (or any officer only section, I guess), regardless to their rank. Six years after the recruitment, their program is completed to become a Commissioned Officer (Acting Sub-Lieutenant/Ensign for the JMSDF and Second Lieutenant for the JASDF). Also, the JGSDF and old Japanese military had these kind of cadet programs, which the system might be different. US Army hires same High Graduates to make them helicopter pilots by appointing them as Warrant Officer 1, joining the WOCS.