According to us, it is highly unlikely that Chopin deleted on purpose the 
sign in the base text to FE or while proofreading this edition. It would mean that he resigned from the characteristic echo effect while repeating the motif one octave higher, an effect Chopin suggested – with the use of in bar 23 and 43 – as one of the first dynamic changes introduced in [A] still before performing Stichvorlage copies (both in GC are written with the copyist's hand). Therefore, we are probably dealing with the engraver's oversight.
See b. 17-19
Compare the passage in the sources »
category imprint: Differences between sources
issues: Inaccuracies in FE
notation: Articulation, Accents, Hairpins