IMHO TIME is not critical for you. If you are talking NROTC, you really can contact, ask to apply, and interview during the summer. Not sure if ALL incoming Mids this year must attend NSI or not. Last year College Programmers for the most part were not sent to NSI due to funding and personnel issues. My son has told me this year things may be different, but again sometimes it depends on the size and funding of the Unit you want to attend. For reference, last year my son didn't even consider NROTC until he went for orientation at his University in mid April, we then called the Unit (located at a sister school) received a tour and briefing. Son then came home impressed, and in late May after numerous conversations with his advisor at the Unit, finally decided to join NROTC (USNA last year did not offer his major) because his advisor and Commanding Officer were so helpful and supportive. He now LOVES NROTC, is thinking about applying for a two or three year "side load scholarship" (he has a full ride at his chosen University) and has made friends and support as a "Programmer".
The only disadvantage in not being a scholarship participant is sometimes Summer Training Programs in NROTC are not offered to Programmers depending on cost and personnel allotments. The only "requirement" as of now is ALL participants must complete the "Summer Cruise" to Commission. Hopefully this will change and programmers will get the same training as scholarship members. NROTC Programmers need to obtain a two year scholarship or Advanced Standing to continue into their 2C year. Scholarship students are already set to Commission upon completion of NROTC and graduation from college.