In AI and FE (→EE,GE1→GE2→GE3) there is no 
before the last semiquaver in these bars. It is most probably a mistake by Chopin, as there is no reason to change the figuration contour so clearly here, in addition, suggesting the C
major key. The inaccuracy was not noticed and corrected until GE4 (→GE5).
Compare the passage in the sources »
category imprint: Interpretations within context; Differences between sources
issues: Omissions to cancel alteration, GE revisions, Errors of A
notation: Pitch