Issues : Chopin's hesitations

b. 33

composition: Op. 28 No. 15, Prelude in D♭ major

C-c in A (→FCGE1, →FEEE)

E-c in FED, FEJ, FES & GE2 (→GE3)

..

The published version of the last L.H. crotchet, a C-c octave, is most probably a result of a correction, which is revealed by the way it was written down in A – the bottom note is at the same pitch as the three E notes in b. 32-34 (as well as the ledger lines of the three D notes), while the ledger line placed above it differs in the thickness from the adjacent ones, which shows that it was added later. Therefore, it was initially an E-c sixth. In this situation, we consider the correction (performed in all three teaching copies bearing traces of being developed, i.e. FED, FEJ and FES) turning the octave back to a sixth to be Chopin's final decision (probably), presumably taken after multiple trials.
The fact that GE2 includes the version passed by Chopin to his pupils might indicate that the publisher had contact with a person from Chopin's circle, someone who knew about that correction – it seems rather unlikely that the reviser introduced such a change without any source indications. However, the octave was perhaps deemed mistaken because in this entire phrase, all the remaining c notes of the upper voice are coupled with an in the lower one.
A similar situation can be found in b. 49. 

category imprint: Differences between sources; Corrections & alterations; Source & stylistic information

issues: Annotations in teaching copies , Annotations in FED , Corrections in A , Chopin's hesitations , Annotations in FES , Authentic post-publication changes and variants , Annotations in FEJ

b. 49

composition: Op. 28 No. 15, Prelude in D♭ major

C-c in A (→FCGE1, →FEEE)

E-c in FED, FES & GE2 (→GE3)

..

This bar is a literal repetition of b. 33; as was the case with that bar, Chopin signalized a change of concept of the last crotchet with compliant corrections in the teaching copies. The changed version was also introduced by GE2 (→GE3).

category imprint: Differences between sources; Corrections & alterations

issues: Annotations in teaching copies , Annotations in FED , Chopin's hesitations , GE revisions , Annotations in FES

b. 65

composition: Op. 28 No. 15, Prelude in D♭ major

..

In A (→FE,FCGE) the  before the 1st R.H. chord is at the pitch of d1. Chopin's patent mistake was rectified in EE; a respective correction is also in FES. The mistake resulted from rhythmic corrections in the parts of both hands that made Chopin cross out the entire bar and rewrite it on the staves below – in the crossed-out version the  was at the right pitch.
The corrections concerned the 1st L.H. crotchet (illegible) and the 2nd and 3rd R.H. chords – the top g1 note in the chord on the 3rd beat of the bar was crossed out, while in the chord on the 2nd beat it was prolonged to a minim. Therefore, it is an example of Chopin's hesitation; in the final version, he returned to the initial concept.

category imprint: Interpretations within context; Differences between sources; Corrections & alterations; Source & stylistic information

issues: Corrections in A , Chopin's hesitations , Errors resulting from corrections , Terzverschreibung error , Deletions in A , Accidental below/above the note