Experimental Factory

[GamerDreams2019ns]

I noticed playing against A.I. UEF faction, they can build different type of Experimental Factory eg. Legion HQ: Experimental Factory. In the build menu, they have Air and Land units.

Whereas I can only build "Gantry Experimental Factory" which has only Land units. I can enable the Air units on the left hand side menu but then the Land unit build Q will be lost. I can't mix them together ??

Is there any way I can build a Legion HQ: Experimental Factory ?

Thanks