The only Bronycon I've been to was the one close to me, in Secaucus for Bronycon Summer 2012. I only went there for the Saturday because it was my first ever convention. It was right after my 17th birthday so it was perfect. I had been to the Meadowlands Exposition Center two years earlier for Pokemon VGC 2010 where they distributed Shiny Eevee, so I knew exactly where it was and I had my parents take me there.
I hung out with an internet friend all day on the very warm, beautiful summer day. We sat at a few panels, I remember we saw literally the last few minutes of the musicians panel. There were many highlights for us on this day. Equestria Inquirer did an interview with Amy Keating Rogers, and I didn't find out until later when it was posted to Youtube, that me and my friend are in the background of that interview walking to the autograph line after we ate lunch. But boy, let me tell you. The autograph line was AWFUL. This was at around 2:15 pm. We went on line to meet Andrea Libman, and she had 2 different autograph signing times after we entered the line. The line was massive, but memorable. On line, I had accidentally dropped my con bag below a ramp, and a generous person in front of me went down to grab my bag and give it back to me. Very nice and thoughtful of him. There was this Discord cosplayer that I remember, I took a picture of him but I can't remember where I saved it.
3 and a half hours later, we made it far enough in line to see the autograph table. That's right, we were still in line. Convention staff asked us who we were lined up to meet, and we said Andrea Libman. They replied, "Oh, Andrea isn't here anymore. You missed her." It wasn't me and my friend who missed her too, a kid next to us also missed her. I told them how we were waiting in line for the past 3-4 hours and that this was my only day of the convention, so the staff was generous enough to go upstairs and bring Andrea Libman down special for the three of us. I think I got her to sign a Pinkie toy. That was more than enough for me, generous as everyone was :).
Luckily, the next year during Big Apple Ponycon 2013 I got to have a proper introduction with Andrea Libman and I got a picture with her. All's well that ends well!