Piano Forum

I've searched this forum before asking this question and only found one post, which didn't discuss it in any detail.

I have several editions of Chopin Op. 28/20.  My question is in reference to the top note of the chord on the fourth count of measure 3.  Every edition I have (except one, Keith Snell) has an E natural as the top note.  The E natural is not written with its own accidental, but is played as a carry over from the E natural contained in the C7 chord on the second count.  However, the Snell edition specifically shows an E flat as the top note of of the final chord in measure 4.  Can anybody explain?  Which note is correct, E natural or E flat?  Incidentally, some of these editions have accompanying CDs.  The performances on the CDs agree with the accompanying edition.   Is this an accepted variation, or have I merely stumbled onto something that everybody else already knows?  Please go easy on me.  I'm a jazzer.