If the recruit had you on the consideration list after signings and you're only up against the SIM, then they will start recruiting other undecided recruits to fill their openings (i.e. even though they are leading on this recruit, they aren't going to take a walk on if they lose said recruit). Once all of their openings fill, you then become the only school being considered (the recruit will sign immediately if you've offered a schollie, otherwise you'll get a scholarship mail indicating you are now leading being the only school he's considering now that the SIM has filled all their openings).
This only occurs the morning after signings begun (when the SIMs begin putting their secondary effort to fill any openings that didn't get filled immediately after signings).