In A the slur at the end of bar 252 (the last one on the page) indicates an intention to lead it to the next bar, where the slur's ending was not written though. Perhaps it was the reason, together with an interrupted continuity of the sign caused by an uneven ink outflow, why the slur was shortened in the editions.
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category imprint: Graphic ambiguousness; Differences between sources
issues: Inaccuracies in GE, Inaccurate slurs in A
notation: Slurs