A fascinating report on the British 1912 manouevres can be found on the following links:
https://canadaatwarblog.wordpress.com/2015/06/06/canadian-officers-notes-on-british-army-manoeuvres-sept-16th-19th-1912-part-i/ (https://canadaatwarblog.wordpress.com/2015/06/06/canadian-officers-notes-on-british-army-manoeuvres-sept-16th-19th-1912-part-i/)
https://canadaatwarblog.wordpress.com/2015/06/07/canadian-officers-notes-on-british-army-manoeuvres-sept-16th-19th-1912-part-ii/ (https://canadaatwarblog.wordpress.com/2015/06/07/canadian-officers-notes-on-british-army-manoeuvres-sept-16th-19th-1912-part-ii/)
A report on 1912 Foreign Army manouevres can also be purchased from here and looks to be very interesting reading:
https://www.naval-military-press.com/product/report-on-foreign-manoeuvres-in-1912/ (https://www.naval-military-press.com/product/report-on-foreign-manoeuvres-in-1912/)
Given I am currently reading Max Hastings account of the first year of WWI, the above should be interesting in light of what happened a few years after they took place. Also the British manouevre is just begging to be wargamed.
Another great find Steve
I should have mentioned that I came across the above via Bob Cordery's excellent Blog:
http://wargamingmiscellany.blogspot.com/2021/03/wargaming-1912-british-army-manoeuvres.html (http://wargamingmiscellany.blogspot.com/2021/03/wargaming-1912-british-army-manoeuvres.html)