The slur, drawn fairly precisely in A, was copied inaccurately into GE, which could be attributed to the manner of the engravers of the German edition. The earlier beginning of the slur may be nonetheless deemed accepted by Chopin, who left that detail unchanged when proofing FE, despite the fact that another correction was actually made for that slur (i.e. linking to the subsequent one). Compare a melodically and pianistically smoother transition to the next bar in the L.H. part also introduced in the proofing of FE.
Compare the passage in the sources »
category imprint: Differences between sources; Corrections & alterations
issues: Inaccuracies in GE, Authentic corrections of FE
notation: Slurs