https://www.wqxr.org/story/why-do-we-tune-a-note-pitch/
A great short overview of how and why A = 440Hz was chosen as the standard tuning note.
By Robert Stephenson, Oboe Professor, University of Utah
Flute Talk Magazine, October 2011
“People often ask why musicians tune to “A”. The most obvious reason is that it is a note all string instruments have in common as an open string. Because of the overtone series, it is a note that enables string players to successfully tune the other strings”.
“The oboe gives the A in an orchestra. The distinct oboe tone allows other musicians to hear it clearly, and the oboe is seated in the middle of the orchestra. The oboe’s pitch is also more stable than other woodwinds which are more easily affected by hot or cold temperatures”.
“In 1917 the American Federation of Musicians adopted A-440 Hertz (440 cycles per second) as the standard and in 1939 the International Standards Association also adopted this standard”.
https://www.mentalfloss.com/article/547437/why-orchestras-tune-to-440-hertz-a-note
A sort, interesting look at “A” as an orchestral tuning note:
“Musicologist Bruce Haynes explained in his book, A History of Performing Pitch: The Story of ‘A.’ In the 17th century, that a French performer might tune his or her instrument a whole tone lower than their German colleagues. The standards could even change from one town to the next, affecting how music written in one location might sound when played in another.”
Bruce Haynes (2002). History of Performing Pitch: The Story of “A”.
Scarecrow Press. ISBN978-0-8108-4185-7.
https://www.dolmetsch.com/musictheory27.htm
A quite detailed history of pitch with support references for you to investigate. Here is a flute moment on this site:
“Once the Hotteterre family had redesigned woodwind instruments to be made in sections rather than in a single piece, transverse flutes could be made with extra sections which, if longer, lowered or, if shorter, raised the pitch of the instrument. An adjustable plug in the head section was used to correct the tuning and speaking properties of the flute as the middle sections were exchanged.”
http://www.oldflutes.com/baroq.htm
For more information on flutes with extra exchangeable sections to be able to change pitch look for flutes with “corps de rechange”.
http://www.mcgee-flutes.com/classical.html
“Pitch was not standardised in the whole period of the conical flute, and it was common to have interchangeable upper bodies (corps de rechange) to permit tuning to different standards. Some flutes had up to 7 corps. By the start of the 19th century, the tuning slide began to supplant the corps.”