Oracle Linux 8 grub error "kernel too small"

Summary:

OCI instance running OL8 with dnf-automatic configured to auto-upgrade the packages. Woke up one morning recently to find the instance not contactable. Cloud console connection revealed it was sitting on the Grub boot menu, but selecting any option returns the following:

error: ../../grub-core/loader/efi/linux.c:86:kernel is too small.

error: ../../grub-core/loader/arm64/linux.c:305:you need to load the kernel

first.

Press any key to continue..."

How on earth do I proceed from here?

Content (required):

Available options are:

   Oracle Linux Server 8 (5.4.17-2136.308.9.el8uek.aarch64)

   Oracle Linux Server 8 (5.4.17-2136.307.3.6.el8uek.aarch64)

   Oracle Linux Server 8 (5.4.17-2136.307.3.5.el8uek.aarch64)