It should simply be `--tag-from-label release`; that way you get a list of all possible tags. https://access.redhat.com/documentation/en-us/red_hat_openstack_platform/13/html/upgrading_red_hat_openstack_platform/assembly-preparing_for_openstack-platform_upgrade#annotations:4762f0dc-ab80-43d3-bfe7-72ed81b36821