It is hard to determine whether it was Chopin that introduced the change of key marking – in [A] or proofreading FE – or it was a result of the engraver's error. The error is justified with flats before g
in bar 24 and g1 in bar 25, apparently added in FE just in print. The notation with five flats is more justified from the point of view of the harmonic flow – the key that dominates from bar 22 to the beginning of bar 25 is B minor. In spite of this, in the main text we give the notation of FE (→GE,EE), as Chopin did not take the opportunity to correct it in a proofreading of FE. Cf. the Etude in A major, No. 10, bars 29-31.
Compare the passage in the sources»
category imprint: Differences between sources; Corrections & alterations
issues: Authentic corrections of FE
notation: Shorthand & other