I'm happy to announce that we've updated our CentOS Stream 8 repository pipeline to merge new composes rather than replacing the previous content. This will give users the ability to `dnf downgrade` packages easily. Most packages don't have multiple versions available yet, but going forward more package versions will be added. You can see if a package is downgradable by asking dnf to show the available duplicates.
# dnf --quiet list --available --showduplicates openssh Available Packages openssh.x86_64 8.0p1-5.el8 baseos openssh.x86_64 8.0p1-7.el8 baseos openssh.x86_64 8.0p1-8.el8 baseos
Due to space limitations we won't be able to keep all packages versions forever, but the intention is to have at least one downgrade version available for most packages. This will make it easier for users to identify if a recent update caused a regression and file a more detailed bug report.