The b2 note, featured in GE as the 4th quaver of the bottom voice, is either the original version or, which is much more likely considering analogous bar 623 and 627, a Terzverschreibung error. The traces of proofreading visible in FE prove that the version was initially present also in this edition, but it was changed in the last phase of proofreading.
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category imprint: Differences between sources
issues: Terzverschreibung error, Authentic corrections of FE, Errors repeated in GE
notation: Pitch