There are no accidentals before the last pair of demisemiquavers in A. Therefore, they should be interpreted as c
2 and c3 (the 
before the 5th demisemiquaver of the bar is in force), which is, of course, impossible. In this Prelude Chopin took it for granted that the second and last demisemiquavers in each group are an octave higher than the preceding melodic note, thus he marked precisely only the pitch of the melodic notes (cf. b. 1-4). Therefore, there are no doubts that it is the bottom note that is written correctly, c2, and the inaccuracy concerns the top note, which must be a c3. Interestingly enough, the absence of a 
restoring c3 was not noticed in any of the remaining sources, even in GE2, in which a cautionary was added before c2.
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category imprint: Interpretations within context; Differences between sources; Editorial revisions
issues: Omissions to cancel alteration, Errors of A
notation: Pitch