The top two-bar A slur reaches the 2nd crotchet in bar 166, which is almost certainly inaccurate – cf. the slurs between bars 169-170. The shorter GE slur (→FE,EE,IE) is an example of adjusting a mark to quaver beams.
The easiest explanation for the absence of the short c2-d2 slur in the editions would be an oversight, although the fact that all similar slurs were omitted in this fragment may point to a conscious strategy by the engraver of GE, which was supposed to make his work easier.
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category imprint: Differences between sources
issues: Errors in GE, GE revisions
notation: Slurs