This is a good question, as I was wondering the same thing. My transcripts and LORs have already been received by LSDAS, but I'm not taking the LSAT until October 2nd. I figured I'd complete all the applications now using the LSACD, then send them the moment my LSAT score was posted. After all, without the LSAT score, you're likely to receive a form letter from the school stating that any admission decision will be postponed until they can verify your score.