In FC one can see deletions of dynamic indications – 
in bar 15 and 
in bar 17. It seems to prove a radical change of the dynamic concept of this fragment (probably until bar 23, in which there is 
), yet it is possible that Chopin only thought that it is not the only possible concept and he did not want to impose it upon the performers. Resignation from these indications can also be explained taking their placement as the starting point – both were written more or less under the 2nd beat of the bar, hence they could have referred to the extended passages, filling the sound of the accentuated notes opening the bars. The composer could have then assumed that such an evident attenuation is not necessary in order to achieve an effect of the phrase's continuity.
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category imprint: Corrections & alterations; Source & stylistic information
issues: Authentic corrections of FC
notation: Verbal indications