It is a revision and completion of the Sonata in D-flat major D 568.
The D-flat major version was composed in June 1817, while the E-flat major revision and completion, published in 1829 after Schubert's death as Op.
[1] I. Allegro moderato E-flat major II.
Menuetto: Allegretto – Trio E-flat major IV.
[2] Daniel Coren summarized the nature of the recapitulation in the first movement of this sonata as "syncopated primary material".