When I was at USNA I knew of about 6 folks who were either kicked out or left on their own that reapplied and got back in. I think what they did outside of USNA is what got them back in. They found USNA alumni and officers to mentor them, they performed extremely well at their colleges and made their case to anyone and everyone who would listen. I think the bottom line since yours was academics is what will you have done to fix this issue? I think your grades at a university are the thing that you must nail in order to show that this will not be a problem and even have a shot. I think its not only grades, but showing time management skills and having great grades while volunteering, working, etc. Talk to an ALO and admissions, lay the ground work now for what might be a 1-2 process to show you can return and thrive at USAFA.