Chopin's intention in relation to 
at the beginning of the bar is unclear. It is both in FE and EE, yet in GC one can see deletion of this sign, hence it is absent in GE. It suggests Chopin's intention to withdraw from this indication. However, in FED, bearing traces of development of the Etude with Chopin, is written in pencil for the second time (apart from the printed sign), which has to be interpreted as confirmation of its validity. Therefore, it is possible that Chopin hesitated whether to indicate the absolute dynamics level in this place. It cannot be excluded that the correction in GC is unfinished – was written there only under the 2nd quaver and Chopin could have simply wanted to move it to the beginning of the bar, yet due to distraction he did not write the sign in the new place. This kind of finished shift can be seen in bar 43, in which 
written by the copyist under the 2nd quaver was deleted by Chopin and added at the beginning of the bar.
See b. 17-19
Compare the passage in the sources»
category imprint: Differences between sources; Corrections & alterations
issues: Annotations in teaching copies, Annotations in FED, Authentic corrections in GC
notation: Pitch