This happens with any air unit that has the "Divide Unit" button available, but in this case we'll examine the 83rd IF Chutai that starts in Hankow. First look at all the pilots and note that none have a rank higher than 2nd Lt (the unit commander is a Major, but not an active pilot). Click the "Divide Unit" button, then "Rebuild", and take another look at the pilots list. The two chosen to lead the "B" and "C" subunits were promoted to MGEN and COL respectively. In fact you can divide any army unit and at least one of the pilots will be promoted to Major General. If you divide up many of your air units (and I do), the Army ones in particular start to accrue a lot of ridiculously over-ranked pilots.
Navy units have a similar issue, but at least with those the promotions tend to stay at lower levels. Assuming the Devs really did want to see pilots promoted with every use of the Divide Unit button, at least it wouldn't look so ridiculous if the code for promoting Army Pilots would match that of the Navy.
