That controls the rod diameter.
Is your issue on 4” with the incorrect hanger? I just removed the 3-1/2” hanger from the PL. Think this started in the ‘19 release.
I am getting it on multiple sizes. 3/4 is getting a 1/2, 4 was getting a 3-1/2, there were others.
I have a hanger specifically for CI with no 3-1/2 size.
I got the standard "We're working on it. . .' when I contacted Autodesk.