The entry in FES is certainly made with Chopin's hand. The addition in FEJ is slightly less characteristic, yet it most probably also comes from Chopin. In spite of that, according to us, the change of the dynamics of the ending is to be considered to be an authentic variant and not a definitive withdrawal from the original concept.
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category imprint: Differences between sources; Corrections & alterations
issues: Annotations in teaching copies, Annotations in FES, Authentic post-publication changes and variants, Annotations in FEJ
notation: Verbal indications