We need to upload the bootloader on aarch64 machines that were booted originally with RHEL8 (i.e. the RHEL 8 version of the UEFI bootloader). See https://issues.redhat.com/browse/OCPBUGS-54594 for more details.

The fix in https://github.com/openshift/os/pull/1795 fixes it for any upgrading nodes but new nodes that are added to a cluster started from 4.11/4.12 bootimages and then imediately pivoted to 4.19+ will need some sort of intervention.

The proposal for the bootimage+pivot problem is to:

1. Create a KCS article instructing cluster admins to update bootimages to 4.13 or newer.
2. Create an admin-ack in the console verifying aarch64 cluster admins have read the KCS article.