The other big change is unsurprisingly AI control. Air units have no individual command structure; instead a stack of air units is always classed as a brigade. Thus any HQ in the chain of command can have air support attached to them. When on manual control this doesn’t actually mean anything as you order around the air units yourself. However when on AI control this can allow you to better control your air assets. Let’s say you have three army groups on a front but all your offensive objectives are in front of only one of those army groups. You can assign air units for the sole use of this army group instead of the whole theatre, focussing air power over the area you wish to attack instead of it being spread over the whole theatre.
Now if we reconsider our example and say you wanted to control the offensive army group yourself, you can assign air power to the army groups you want to hand over to the AI and allow them to use themselves without you having to manage both your offensive and air power over the whole theatre.
Now these examples are for large formations, but air power can even be assigned down to corps level. So if you think that a corps or an Army needs some special help for whatever reason you can detach the air power from the high level command and assign down for the exclusive use of this formation. When the help is no longer required simply detach again and reassign up the chain the command.