Something I did last year. I was reading Warrior: En Garde while I was working on this piece. It was originally going to be about Melissa Steiner being in the middle of everything (so the famous wedding cake and Sword of Damocles were always going to be a part of it). As I read on, I became intrigued by the Jeana Clay character, so I swapped her out before I finished the first novel.
Which brings me to the "mistake" of the piece. I scouted ahead on Sarna to get some broad strokes about Jeana and places and people that were important to her, and I wanted to incorporate elements of Daniel Allard into the piece. By the time the two meet, Daniel Allard is already piloting a Wolfhound, rather than the Valkyrie he started with in Warrior: En Garde. But by the time I realized my error at the beginning of Warrior: Riposte, this piece was already finished, so I didn't alter the 'mech.