I'm a bit confused. The first and third movements in the 2 editions I have of the K 545 sonata have no difference at all.
But the second movement has a difference in the development section. Both editions are from the same people who published 19 Sonatas for the Piano where K 545 is Sonata I.
The older edition I have has a few bars of false recapitulation before the whole development repeats. The newer edition doesn't have that, just a true recapitulation after the G minor development.
Why the difference though? I can understand that different editors emphasize different things about Mozart and the only way to get everything is to look at Mozart's original manuscript which I doubt exists anymore for this sonata. I can also understand minor differences from 1 edition to another.
But this is the case of 2 editions from the same publisher being significantly different. Why?