Before the R.H. penultimate quaver Chopin wrote in A a cautionary 
which he crossed out after having checked it was not essential. This proves the intended pitch to be c
-c1 here. Therefore, the EE version is arbitrary – the reviser repeated here his amendment from the previous bar where he added (rightly there) naturals rising c-c1 to c-c1. We add cautionary flats in the main text here as GE2 already has done.
Compare the passage in the sources »
category imprint: Differences between sources; Editorial revisions
issues: EE revisions, Errors in EE, GE revisions, Cautionary accidentals, Deletions in A
notation: Pitch