I guess I did the sign-up incorrectly. I thought that I was to leave a comment on the sign-up post, and while I noticed there were no other comments, I assumed that they were screened and wouldn't appear to anyone but the mods and poster (OK, duh!).
I understand that it's too late for this year, but could you tell me what I was supposed to do?
Also, if you need pinch-hitters, you could just take my original sign-up.