How did Schubert alter the recapitulation in his Symphony No. 5 in B-flat Major?

In the first movement of his Symphony No. 5 in B-flat Major, Franz Schubert altered the recapitulation by presenting the first theme in the subdominant key rather than the tonic key.1

This modification served as a practical, labor-saving device: because the first theme begins in the subdominant, the transition passage—which originally moved from the tonic to the dominant in the exposition—naturally leads the music from the subdominant to the tonic in the recapitulation. This allowed Schubert to place the second theme in the tonic key without needing to rewrite the transition material. This approach reflects Schubert's evolving attitude toward sonata form, demonstrating a departure from the strict harmonic expectations established by his Classical predecessors.12