To work, you need an installed and activated Expert AI mod. Many new historical events in the style of "what if".Developing aviation zones for the US and Canada to make them more user-friendly.Complete reworking of fleet units as far back as 1953.
New weapons that can be produced according to what was actually developed at that time as far back as 1955.New focuses for Czechoslovakia, nationalist and Communist China, Manchukuo, Sweden, and the Russian civil war.In addition, Operation Overhaul adds new focuses, ideologies, and a large number of interesting events. The mod follows realism - all technologies really correspond to the development of those years.
It extends the game's technology tree to the 1960 period. Popular mod Operation Overhaul for the game Hearts of Iron 4.