When interpreted literally, the FE (→EE) marks could be interpreted as 
hairpins (particularly the second mark in bar 317, longer than the remaining ones), and this is how we reproduce them in our transcriptions. The clear difference in the marks' length and position with respect to the A accents probably resulted from the fact that Chopin added them twice and independently – to A and to [FC] or while proofreading FE1. This would support the interpretation of the FE marks as long accents (as the context suggests), hence – accepting their authenticity – we suggest them in this form as an alternative version to the short A accents.
See also the note in bar 318.
Compare the passage in the sources»
category imprint: Differences between sources; Editorial revisions
issues: Long accents
notation: Articulation, Accents, Hairpins