Was getting similar errors on on subsequent `sudo apt upgrade`s - worked around by freeing boot space as suggested in https://bugs.launchpad.net/ubuntu/+source/initramfs-tools/+bug/1899907
Was getting similar errors on on subsequent `sudo apt upgrade`s - worked around by freeing boot space as suggested in https:/ /bugs.launchpad .net/ubuntu/ +source/ initramfs- tools/+ bug/1899907