Qt Installer Framework: Specify MacOS SDK version to use when building installer

[Timothy]

I am building a Qt app with XCode and targeting MacOS SDK 10.11, to allow users who are not on the most recent OS version to run the app. This works and the app itself runs on Mac OS 10.11+, but when I package the app using the Qt Installer Framework, the SDK used appears to be the latest version, which means that the installer app will not run on anything but the latest MacOS version.

Is there anything I can do to configure binarycreator to use a different MacOS SDK version when building the installer app? An environment variable perhaps?