Only bootc images will be supported in confidential clusters. Therefore, on a cluster version upgrade, the MCO should rely on the bootc upgrade path. Further, the upgrade path for confidential clusters should have no reliance on rpm-ostree. This task involves setting the upgrade path to use bootc whenever a confidential cluster is scheduled for an upgrade.

Note that the work for supporting a bootc-only upgrade path was previously refined in the MCO-1238 epic. Completing this initial confidential computing phase requires completion of that bootc work.

Done when:

• A cluster in confidential mode uses the bootc path for cluster version updates.
• There is no reliance on rpm-ostree for cluster version upgrades for clusters in confidential mode.