You could definitely bake it today. You may want to wait till tomorrow to frost it, but
As Traca said, the frosting is very very sweet, therefore it should hold up fine, since sugar is a preservative and since the butter is already clarified. (I'm sure Maya's grandmother made it a day ahead for the various picnics and socials described in her books, and the recipe pre-dates modern refrigeration. I've always made it a day ahead and if there were leftovers I could tell you about the second day--but there haven't been any.)
If you frost it ahead of time just be sure to cover it well in a cake dome or something similar--the frosting can dry out and get crusty with it's high sugar content.
Sorry I missed the first request. I was busy feeling important. I hope you threw caution to the wind and baked it anyway.