Tchaikowsky- Piano Concerto No. 1 in B-flat

I heard Brett play this piece on Sunday’s Concerto Concert Concert, and he did a heck of a job. The transition between a clear, tonal motive and fast-moving scalar passages with no clear direction is key in the structure of this piece. It begins in periodic fashion repeating the initial A motive four times. The 1st and 3rd end in weak cadences, and the 2nd and 4th end in a stronger one, I believe a PAC. These two parallel periods constitute the first a section. The motive is then developed quickly for one phrase with a new tonality and raised register. It then comes back down to repeat the original a section. These three sections as a whole make up entire first A section, which is in a sort of rounded binary form. Then comes a textural change to the motive with a diminuition with very fast notes played in between. In this B section there are also virtuostic parts in the piano section with fast moving multi-voice scales, and the Orchestra maintains the slower moving melody. The A then comes back twice before another scalar transition and another new section. In this section, the orchestra plays a fragment of the motive over and over in an ascending sequence, getting louder and fuller each time until leading to a climactic, virtuosic piano passage over the motive to terminate the piece. So, in all, I’m not sure I necessarily interpreted the form of this piece correctly, as it seems to include attributes of rounded binary, composite ternary, and rondo