It is pretty well documented on how pilots dealt with covergence, when a USAAF pilot had some hours in combat (nothing to do with ace pilots) he generally got his own plane and could do what he liked to do with it , he sorted it out with the crew chief, that was the "owner ". They had their own ideas about these things. They chose one convergence and adjusted it to optimal and sticked with it for the duration. Not for every mission. Same with UK pilots, every now and then someone else flew their plane , and they have to fly other planes, not sure what was done about it then