The design doc for ImageDigestMirrorSet states:
"ImageContentSourcePolicy CRD will be marked as deprecated and will be supported during all of 4.x. Update and coexistence of ImageDigestMirrorSet/ ImageTagMirrorSet and ImageContentSourcePolicy is supported. We encourage users to move to IDMS while supporting both in the cluster, but will not remove ICSP in OCP 4.x.".
see: https://github.com/openshift/machine-config-operator/blob/master/docs/ImageMirrorSetDesign.md#goals

see also:
https://github.com/openshift/enhancements/blob/master/enhancements/api-review/add-new-CRD-ImageDigestMirrorSet-and-ImageTagMirrorSet-to-config.openshift.io.md#update-the-implementation-for-migration-path
for the rationale behind it.

but the hypershift-operator is reading ImageContentSourcePolicy only if no ImageDigestMirrorSet exists on the cluster, see:
https://github.com/openshift/hypershift/blob/main/support/globalconfig/imagecontentsource.go#L101-L102

    4.14, 4.15, 4.16

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    1. Set both an ImageContentSourcePolicy and ImageDigestMirrorSet with different content on the management cluster
    2.
    3.    

the hypershift-operator consumes only the ImageDigestMirrorSet content ignoring the ImageContentSourcePolicy one.    

since both ImageDigestMirrorSet and ImageContentSourcePolicy (although deprecated) are still supported on the management cluster, the hypershift-operator should align.    

currently oc-mirror (v1) is only generating imageContentSourcePolicy.yaml without any imageDigestMirrorSet.yaml equivalent breaking the hypershift disconnected scenario on clusters where an IDMS is already there for other reasons.