You might get a callback, happened to me (still did not attend because I went to NASS). Being originally denied to SLE did not hurt my chances of getting in; in fact, I got an LOA in September of my senior year. Best wishes.
I was originally denied from USMA's SLE (got a callback but didn't attend because I went to NASS and girls state), I didn't even apply to USAFA's. With that being said, I got LOA's and appointments to both USMA and USAFA and didn't even finish my USNA app. I wouldn't overthink it too much. (I am...
I'm in the class of 2020 (a plebe this year). I received my LOA on September 3rd, 2015 and received my appointment just before Christmas. You will get yours as long as you stay healthy and don't do anything stupid. It should come at the end of January at the latest.
I was denied SLE at first, got a call back (but was already going to NASS and girls state), and then finished my application in August and received an LOA on September 3 this past year. Don't think too much into it!