First Intermission is the former collective name for what is now:
After Book 1: The Battle for Gobwin Knob's comic pages were originally finished, there were a series of text updates initially referred to as Summer Updates 2009 because it was indeed Summer of 2009. These were later organized on the website under an archive section named First Intermission, and treated as a sort of Book 1.5.
In preparing the comic for physical book printing, the First Intermission pages were split up and published with Book 1: The Battle for Gobwin Knob as epilogues and Book 2: Love is a Battlefield as prologues. In August 2014 the website was updated and reorganized, and these pages were included with their book's archives.
The Erfwiki had already grown around First Intermission as an organizational feature by this point. Therefore it wasn't until December 2014 that a Titanic effort of around 400 edits was made to Retconjure the wiki to reflect the current archive and printed books.