Beginning from the sixth d flat2-b flat2, the four subsequent two-chord notes are written in A in the manner described in a remark to bar 11. Also here, the notation is surely not what Chopin ultimately intended to have, as he abandoned it when writing the subsequent two-note chords.
The reason behind the change of the initial one-part notation into a two-part one was probably the augmented unison a flat2-a2. Chopin learned on the example of earlier published works, Ballade in G minor op. 23 and Variations in B flat op. 12, that the single-voice notation easily led to ambiguities and errors (in the Ballade in bar 171 the note b2 in the 4th crotchet of the quintuplet was printed in FE w in such a manner that in GE (based on FE) it was allocated to the 5th crotchet; a similar misunderstanding must have also taken place in the Variations, in bar 110).
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category imprint: Interpretations within context; Corrections & alterations
issues: Corrections in A
notation: Rhythm