According to us, the 
indication is to be interpreted as valid already from the beginning of the bar. It is one of examples of the manner of introducing indications within the scope of their validity, used sometimes by Chopin, particularly in his earlier works. In GE (→FE→EE) was most probably linked with the entrance of the L.H.
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category imprint: Differences between sources
issues: Inaccuracies in GE, Centrally placed marks, Inaccuracies in A
notation: Verbal indications