In A one can see that the 
mark under the 1st crotchet was written over an earlier mark, most probably 
. Therefore, it is likely that 
was added only just at the stage of writing pedalling marks, which was generally the final stage of developing a manuscript. It could explain the uncommon placement of that indication, which, after all, cannot refer to the L.H. only – while entering pedalling marks Chopin probably followed only the L.H. part, as a result of which, by placing before, and not under the chord, he could have had an impression that the range of that indication encompassed the entire sonic structure of this place. Another reason could have been the crossings-out preceding that bar and the resulting lack of space, as a result of which it was not possible to insert between the staves.
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category imprint: Interpretations within context; Differences between sources; Corrections & alterations; Source & stylistic information
issues: Corrections in A, FE revisions, Fontana's revisions
notation: Verbal indications