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b. 255

composition: (Op. 4), Sonata in C minor, Mvt IV

b-b in A, amended version

b-b in A (original version, contextual interpretation) & GE (→FE,EE,IE)

..

The version of the 2nd half of the bar in A, pianistically and harmonically questionable, is probably an example of a "correction" (the change of  to , probably performed in a hurry), which resulted in a greater mistake than the one that was supposed to be corrected – the absence of the  restoring b on the 5th quaver. The initial notation reveals that Chopin approached this place in the same way as he did with the similar situations in bar 254 (as well as 250 and 253), where the flats, although undoubtedly necessary, are only of a cautionary nature.
In GE (→FE,EE,IE) the initial text was restored, supplemented by the necessary

category imprint: Interpretations within context; Differences between sources

issues: Corrections in A , Errors resulting from corrections , GE revisions , Foreign hand additions in manuscripts , Deletions in A

b. 259-260

composition: (Op. 4), Sonata in C minor, Mvt IV

..

In A in both bars Chopin omitted the naturals restoring f3. The accidentals were added in GE (→FE,EE,IE).

category imprint: Interpretations within context; Differences between sources

issues: Omissions to cancel alteration , GE revisions , Errors of A

b. 259

composition: (Op. 4), Sonata in C minor, Mvt IV

..

In the main text we include the cautionary  to e3 added in GE (→FE,EE,IE).

category imprint: Differences between sources; Editorial revisions

issues: GE revisions

b. 261-262

composition: (Op. 4), Sonata in C minor, Mvt IV

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In the L.H. part EE1 overlooked both flats to d2 in these bars. The mistakes were corrected in EE2.

category imprint: Interpretations within context; Differences between sources

issues: EE revisions , Errors in EE

b. 262-263

composition: (Op. 4), Sonata in C minor, Mvt IV

..

In the main text we omit the unnecessarily repeated  to d3 at the end of bar 262; the accidental was also omitted in GE (→FE,EE,IE). On the other hand, we add a cautionary  to a2 at the beginning of bar 263.

category imprint: Differences between sources; Editorial revisions

issues: GE revisions , Cautionary accidentals