This site introduces unknown Emanuel Bach (C. P. E. Bach).
ChatGPT4o writes as follows (please note that it may not be accurate):
Emanuel Bachʼs Oboe Concerto in E-flat major, Wq. 165 (H. 468), composed in 1765, is a significant work that demonstrates the development of his concerto style. This piece is characterized by expansive melodic lines and continuous development, marking a departure from the Baroque form and hinting at the transition to the Classical era. The first movement begins with a bright and lively theme, where the oboe solo showcases rich expression with brilliant ornamentation. In the second movement, the freedom of form is particularly notable, with the traditional ritornello form being weakened. The tutti sections in this movement are simplified, and the extended solo passages emphasize a meditative character. Additionally, a sudden modulation to E-flat major at the end of the movement facilitates a smooth transition to the third movement. The third movement is a light and elegant finale, bringing the entire piece to a bright conclusion. This concerto highlights the expressive capabilities of the oboe and the evolution of Emanuel Bachʼs compositional technique, and it is also known for being later arranged into the Keyboard Concerto Wq. 40 (H. 467).
The Oboe Concerto Wq. 165 was arranged from the Keyboard Concerto Wq. 40.
Particularly notable is the increased interest in large-scale continuity throughout the work, as seen in the form of the second movement, titled Adagio ma non troppo in A minor. In this movement, the clear ritornello form expected in both fast and slow movements is weakened. The second tutti section is very short, limited to the opening part of the first ritornello, and the third ritornello is almost omitted, reduced to a simple tutti insertion in the middle of a long final solo section. However, most noteworthy is the final part of the tutti, which ends in E-flat major instead of reaffirming the key of C minor. This key had not appeared earlier in this movement and is used to facilitate a smooth transition to the final movement.