This is a charming and energetic movement, likely an early composition by Mozart, displaying his developing mastery of form and melody. It features brilliant passagework contrasted with lyrical moments.
Requires a balance of clear articulation for rapid passages and a singing tone for lyrical sections.
Allegro in B-flat major (K.372) is rated Henle level 4 of 9 — intermediate repertoire, roughly ABRSM grades 5–6. In the RCM system it corresponds to about level 7.
You should be comfortable at Henle level 4 — meaning you can already play level 3–4 pieces cleanly. Learning it one level early is possible as a stretch piece, but more than that usually leads to months of frustration.
A typical performance of Allegro in B-flat major (K.372) lasts about 5 minutes.
Allegro in B-flat major (K.372) is available as free public-domain sheet music on IMSLP — the score is linked directly from this page.