Nibs, you can show up for the open day without receiving any notification from them, unless they specifically send you an email saying you don't qualify, in which case I would find out why and/or still show up and give it a shot!
Are you applying for the OD in DC on Feb 26th? that's the one I'm going to! Don't worry about your height, as long as you can reach the limit you will be ok (most girls are much shorter and they make it)
cheers
-Flygirl22