The octave sign added in FEH most probably defines an authentic variant. According to us, it is much more likely that it was meant to move the entire figure of both hands by an octave, and not only of the R.H.
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category imprint: Interpretations within context; Differences between sources; Corrections & alterations
issues: Annotations in teaching copies, Authentic post-publication changes and variants, Annotations in FEH
notation: Pitch