In FE there are no ties sustaining the upper notes of the octaves in bars 11-12 and 13-14. According to us, the most probable explanation is a misunderstanding at the time of changing the original brief notation of the octaves with the use of 8 under the upper notes for regular notation.
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category imprint: Interpretations within context; Differences between sources
issues: EE revisions, Errors in FE, GE revisions
notation: Rhythm