Naaaaaaaaaaah .... NROTC used to get either/or commissions. Same for NROTC-Marines at the time ...As far as I understand it, OCS and NROTC officers used to commission as "reserve" officers while USNA commissioned as "regular" officers......
I.e., Regular OR Reserve.
The Regulars came out of the 'regular' 4-year scholarship program ... the Reserves came out of the 2-year program and had to apply for 'augmentation' into the Regulars @ some point in their career, assuming they desired USN vice USNR status (I don't know specifics @ USMC Officer 'augmentation' to regular status back then) ... of course, there were some other 'what if's' and 'mebbe's' .... but that's basically it.