I was trying to sign up this year, and the countdown said I had 15 minutes left but when I checked ao3 it said signups had been closed. I had been without internet for a bit, which was why I wasn't able to sign up sooner, and logged on soon as I could and was excited that I had 15 minutes left to get my sign up on. I'm not sure you can do anything about it now, but I just wanted you to know that I tried. :(