Initially, Chopin wanted to notate in A the transition chords of the 2nd part of the bar without resorting again to the notation with the use of sharps:
We can see in the deleted fragment that having precisely notated the R.H. part (together with performance markings) Chopin began writing the L.H. part but reached the penultimate semiquaver and discontinued the notation that required the use of 3 different double flats. He tried to rework certain notes, e.g. b double flat1 to a1, but eventually deleted the entire fragment and wrote it out again in the form that we know today.
Compare the passage in the sources »
category imprint: Corrections & alterations; Source & stylistic information
issues: Corrections in A
notation: Pitch