Duplicate qml modules in android_rcc_bundle.rcc and backing target (created by qt_add_qml_module)

If I understand this correctly, a qml module (consisting of qmldir, qml, js, ... files) created by CMAKE "qt_add_qml_module" exists in two places (Android only):

• Within the Qt resource inside the lib created by the "qt_add_qml_module" backing target. The module is then located under the path "qrc:/qt/qml/<module_name>" (policy QTP0001 set to "NEW")
• Within the Qt resource created by androiddeployqt (called android_rcc_bundle.rcc). The module is then located under the path "qrc:/android_rcc_bundle/qml"

How I noticed that a qml module was present twice in my app:

I removed the "prefer qrc:/qt/qml" statement in the qmldir file created by "qt_add_qml_module" (during development I want the qml files to be loaded directly from disk and not from the backing target - thus I can reload the qml GUI without recompiling the backing target). Then I deployed the App on the Android device using androiddeployqt ("prefer qrc:/qt/qml" still missing in the qmldir file). Then I got this errors in logcat:

12-29 17:26:15.769 24805 24828 W ONVIFmonitor: [29/12/2023 17:26:15] WARNING  : qrc:/qt/qml/Onvif/Onvif/main.qml:9:1: Type Rally.RallyRootPage unavailable 
12-29 17:26:15.769 24805 24828 W ONVIFmonitor:      Rally.RallyRootPage { 
12-29 17:26:15.769 24805 24828 W ONVIFmonitor:      ^
12-29 17:26:15.769 24805 24828 W ONVIFmonitor: [29/12/2023 17:26:15] WARNING  : qrc:/android_rcc_bundle/qml/MaterialRally/MaterialRally/RallyRootPage.qml: Type Helper unavailable
12-29 17:26:15.769 24805 24828 W ONVIFmonitor: [29/12/2023 17:26:15] WARNING  : qrc:/android_rcc_bundle/qml/MaterialRally/MaterialRally/Helper.qml:4:1: Script qrc:/android_rcc_bundle/qml/MaterialRally/MaterialRally/helper.js unavailable 
12-29 17:26:15.769 24805 24828 W ONVIFmonitor:      import "helper.js" as Helper 
12-29 17:26:15.769 24805 24828 W ONVIFmonitor:      ^
12-29 17:26:15.769 24805 24828 W ONVIFmonitor: [29/12/2023 17:26:15] WARNING  : qrc:/android_rcc_bundle/qml/MaterialRally/MaterialRally/helper.js: No such file or directory
[29/12/2023 17:26:15] FATAL    : "Couldn't create GUI: qrc:/qt/qml/Onvif/Onvif/main.qml:9:1 .... 

as we can see the qml module "MaterialRally" is loaded from qrc:/android_rcc_bundle/qml and not from qrc:/qt/qml, because "prefer" statement is missing and the qml import path "qrc:/qt/qml" has by default the lowest priority of all paths searched by QmlEngine. This is the list of default qml import paths reported by QmlEngine:

"qrc:/android_rcc_bundle/qml", "/data/app/~~RP1KBvueOeSfhxLFGWBJIg==/com.github.tereius-gf7Mxo0T5S2xB5HnmVYx6w==/lib/arm64", "qrc:/qt-project.org/imports", "qrc:/qt/qml"

If I now reorder the list of qml import paths and move qrc:/qt/qml to the front and deploy the app again, everything works as expected and the helper.js file is actually found (the lowercase is on purpose - the helper.js file should not be directly accessible).

This leads to several questions:

• Why is it necessary to have the qml module present twice at two different locations in the app?
• Both qml modules behave different: helper.js file is missing in the android_rcc_bundle but is present in the backing target. Why?
• The android_rcc_bundle is nowhere documented. Why is it needed, what does it do?