I’m not Army ROTC, but one of my friends is a mechanical engineering major and has to take 4.5 years to graduate and he has to pay out of pocket for that extra half a year. It may not work the same in AROTC and maybe my friends example is unique so I am not 100% sure it is the same. I would certainly talk to your unit staff about it though.
DS is also studying engineering and his scholarship was extended from 4 to 4.5 years due to his major (AROTC). He was told early on that it is normal for engineering students to need longer to graduate especially with the extra time demands of ROTC. The Army understands that so extends scholarships up to 5 years.
OK...so OP didn’t say he was studying engineering, so I’m not sure we are answering his question...Why do you need an extension? The Army usually doesn’t extend a scholarship unless there is a need, and the it is known ahead of time that you are in a program that requires additional semesters, like an engineering degree at some schools. If you are at such a school and need the extra semesters you would have normally been awarded the extended scholarship when you received your offer. If you are looking for extra semesters because you have fallen behind or want to pick up a minor you will normally not receive an extension. If you are looking for your 3AD to be upgraded to a 3.5 that’s a whole different issue and what AROTC-Dad is talking about.