OnlineBookClub.org

I noticed in the guidelines it mentions that the gender neutral terms should be used for the author unless you know for sure of the gender. Even though I thought it was "she" I wanted to be extra cautious and use "they ". This counted towards my score and I would like more clarification on this.

If you're not sure if the author is male or female, you should use "they." If it's obvious that they are female (there is a picture or you can tell from their bio), then you can use traditional pronouns. It sounds like you're tracking.