The 
mark is placed in A between the pair of the final chords, hence the fact that FE1 assigned it to b. 46 is formally justified – markings are not retroactive. However, it seems much more likely that Chopin applied here the manner of writing indications within the scope of their range, and the mark is supposed to concern both chords, as it was performed in FE2 (→EE). Cf., e.g. the Concerto in E Minor, Op. 11, 1st mov., b. 16.
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category imprint: Differences between sources
issues: Inaccuracies in FE, FE revisions, Errors of FC, Centrally placed marks
notation: Verbal indications