One can see Chopin's proofreading in the version of FE, since a
as the penultimate note reasonably combines with the 1st chord in the next bar. However, the argument brought forward in the note concerning the previous figure suggests a Terzverschreibung error, which is more likely, according to us. It was considered a mistake already in EE, in which a was changed to f.
Compare the passage in the sources »
category imprint: Differences between sources
issues: EE revisions, Terzverschreibung error, Authentic corrections of FE
notation: Pitch