Issues : Corrections in A

b. 1-2

composition: Op. 28 No. 21, Prelude in B♭ major

Slur from to c1 in A

Slur from B1 to c1 in FC (→GE)

Slur from to B in FE (→EE)

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In the main text we give the slur of FE (→EE), since the vast majority of subsequent slurs, present in a similar context, is led to the 1st quaver in the next bar in A – out of 13 slurs in b. 1-12 and 15, it is only the slurs in b. 1, 8 and 10 that end on the 6th quaver; two (in b. 6 and 9) are ambiguous. We consider all the above slurs to be inaccurate, since the differences in the range of slurs are not related to the structure of motifs, e.g. the shorter slurs in b. 1 and 8 are opposed by the longer ones in similar figures in b. 2 and 7. Moreover, in A one can see corrections – the slurs in b. 4-5 and 5-6 were being extended (in b. 3-4 probably too). Along with the crossed-out staccato dot at the beginning of b. 2, it may indicate that the concept of markings of those figures changed from  to . Consequently, the aforementioned shorter slurs would be uncorrected elements of the initial slurring.
The slur beginning from the 1st quaver is an inaccuracy of Fontana, repeated in the next three bars too.   

category imprint: Differences between sources

issues: Corrections in A , FE revisions , Omitted correction of an analogous place , Inaccuracies in FC

b. 1

composition: Op. 28 No. 21, Prelude in B♭ major

category imprint: Corrections & alterations; Source & stylistic information

issues: Corrections in A , Deletions in A , Changes of tempo markings

b. 1

composition: Op. 28 No. 21, Prelude in B♭ major

category imprint: Corrections & alterations; Source & stylistic information

issues: Corrections in A , Deletions in A , Changed phrase length

b. 3

composition: Op. 28 No. 21, Prelude in B♭ major

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In A one can see a crossing-out between the  and the 3rd quaver. It was most probably the  before a that was removed (superfluous), yet it seems that, for some reason, Chopin also crossed out the correctly written f-a third, which he then reintroduced next to it. If it was so, the reason could have been, e.g. accidentally blurred noteheads, even partially, as a side effect of removing the natural.

category imprint: Corrections & alterations; Source & stylistic information

issues: Corrections in A , Deletions in A

b. 6

composition: Op. 28 No. 21, Prelude in B♭ major

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The crossing-out in A reveals the initial version of the beginning of this bar: .

category imprint: Corrections & alterations; Source & stylistic information

issues: Corrections in A , Deletions in A , Main-line changes