I was using the original administrator account for posting, and I had one other author who was also set up as an admin. Everything was working fine since December.
Two days ago I created a third user, also setup as an admin. Since then my original administrator account no longer appears in the list of possible authors for posts. Nothing I do can seem to return my account to the author's list. I log out, log back in, nothing.
Any new users that I create appear properly in the dropdown when I am create a New Post.