First off, I think the previous 2 posts are talking about 2 different things. The original post was talking about summer seminar. To lone survivor, I would say that you applied in plenty of time as others who have applied later but still before deadline have been accepted and others who have applied earlier than you are either still waiting to hear at all or wait listed or didn't get in. Its hard to say how the academy has chosen the seminar class--I don't think timing was the issue. Your academics look good--what about leadership, athletics, extracurricular activities, etc.? The academy looks at the whole candidate for seminar just like they do for admittance. A couple people that attended last year mentioned on this forum that they originally were wait listed and ended up getting in. So hang in there!
To KO5791, it sounds like you are talking about regular admission (summer seminar application doesn't open until December I believe and doesn't include a CFA). A benefit to early application for admission (by August/Sept. or so) is that IF the academy deems your file to be very strong, you MIGHT get an LOA (letter of assurance) late in the fall that almost guarantees an appt. IF you get a nomination. (Lots of qualifiers there!) That won't happen if your file isn't complete until Jan/Feb--they're past the point of handing out LOA's by then. But if your CFA practice scores are weak, then I think it definitely is better to work on improving them significantly before submitting them. A weak CFA won't get you an LOA, waiting until later in the application period to submit it won't get you turned down.