The reason I see is because day 4 is story AND copywork (writing the child's narration,) once you're past the first 6 weeks or so? We swapped it at first. Narration, copywork, narration, copywork. Once the extra copywork came up we now do Day 1: Narration AND copywork (Lessons #2&1,)
Day 2: Copywork
Day 3: Narration and first part of writing their narration. (Mine tend toward long narrations.)
Day 4: finish writing narration if it's long. If not, no lesson!