in The letter 'z' in the 
marking was omitted in the first editions of Chopin's works several times – cf., e.g. the Etude in C
minor, Op. 10 No. 4, b. 1.
The erasure visible in A suggests that Chopin initially wrote there a 
, which, in turn, indicates that there is a difference in meaning between and ; however, it is unclear what the difference actually is. According to us, it is likely that could be associated with an isolated or a target accent, after which the current course is not continued anymore. On the other hand, , applied in the Variations much more often and always accompanied by an accent, usually long, or a 
hairpin, generally implements the appoggiatura dynamic scheme – it emphasises the first out of the pair of the concerned notes.
Compare the passage in the sources »
category imprint: Differences between sources; Corrections & alterations; Source & stylistic information
issues: Corrections in A, Errors in GE, fz – f
notation: Verbal indications