I did this during the school year. I e-mailed ahead to attend a class and ended up doing the tour, too. I also dropped in to drop off a LOCI later. Lo and behold, they took me (after a second LOCI, which I PDFed and e-mailed)!
You might definitely make it a chance to drop off your "I will attend if you take me" LOCI, especially if you can think of anything else to add.