Comment 1 for bug 1199982

So it looks like the new packages indeed contain /var/lib/system-image, including /var/lib/system-image/keyrings.

However on my device, I mount an empty directory on /var/lib/system-image on first boot, which means that the keyrings directory can't be found by system-image-cli and results in:
FileNotFoundError: [Errno 2] No such file or directory: '/var/lib/system-image/keyrings/image-master.tar.xz'

system-image-cli needs to be changed to create the keyrings directory when missing.