If you don't care where you sit, it's possible to walk in later in the afternoon, but not at all guaranteed. There's a lot of really competitive stuff in that room on Friday. Lining up overnight may only be required to get a good seat, but you might have to at the very least get there early in the day and sit through panels you aren't interested. This is speculation though, of course, as things always fluctuate. Right now, though, the Friday programming looks way more competitive than Saturday so you likely won't be able to walk in right before the panel.
Good luck, friend, and enjoy the con!