Where "BuildConfiguration.xml" should be located?

It would be worth adding this to the documentation here:

It mentions the locations, but not what happens if there are more than one.

Is it last one wins, or are they merged together with elements from last ones taking precedence? Because it seems from testing that if the AppData/ one doesn’t exist, it always gets created automatically anyway, meaning it would always take precedence regardless of the others?

(from what I could see in the code: it puts each in an array, then parses each one by one, setting values, so it is more of an individual value override system with last values overriding earlier files, but all files sort of merged togetehr)