The version featuring b
resulted from a mistake or inaccuracy by Chopin in [A] – the 
to the 1st third was written there in such a way that both Fontana and the engraver of FE put it before d1, where it has no purpose. It must have been b, which, however, was noticed only in EE.
Compare the passage in the sources »
category imprint: Interpretations within context; Differences between sources
issues: EE revisions, Accidental below/above the note, Errors repeated in GE, Errors repeated in FE
notation: Pitch