The initial version of the ending of the Prelude (which can be deciphered from under the crossings-out in A) differed quite significantly from the final one – the passage reached only D, and the piece ended an octave higher: 
. In that version, it is noteworthy that the passage contains e3, e2, e and E, but not e1.
The next version may have looked like the one presented below: 
. Eventually, Chopin forwent all the aforementioned e notes (he only left E1, which was added later) and added B
1, thus providing the general part of the passage with a homogeneous course, based on the b-a-f-d sequence.
Compare the passage in the sources»
category imprint: Corrections & alterations; Source & stylistic information
issues: Corrections in A, Deletions in A, Main-line changes
notation: Pitch