The following allows you to revert changes (Appstream packages) when upgrading from AlmaLinux 8.7 to AlmaLinux 8.8.
Copy the current configuration and make it the repository file for the previous AlmaLinux release.
sudo cp /etc/yum.repos.d/almalinux.repo /etc/yum.repos.d/almalinux-8.7.repo
Replace all $releasever with the previous AlmaLinux version.
sudo sed -i 's/$releasever/8.7/g' /etc/yum.repos.d/almalinux-8.7.repo
Update the value in the [] tag to the previous AlmaLinux version
sudo sed -i 's/\[baseos\]/\[baseos-8.7\]/g' /etc/yum.repos.d/almalinux-8.7.repo
sudo sed -i 's/\[appstream\]/\[appstream-8.7\]/g' /etc/yum.repos.d/almalinux-8.7.repo
sudo sed -i 's/\[extras\]/\[extras-8.7\]/g' /etc/yum.repos.d/almalinux-8.7.repo
sudo sed -i 's/baseos-source\]/\[baseos-source-8.7\]/g' /etc/yum.repos.d/almalinux-8.7.repo
sudo sed -i 's/\[appstream-source\]/\[appstream-source-8.7\]/g' /etc/yum.repos.d/almalinux-8.7.repo
sudo sed -i 's/\[extras-source\]/\[extras-source-8.7\]/g' /etc/yum.repos.d/almalinux-8.7.repo
sudo sed -i 's/\[baseos-debuginfo\]/\[baseos-debuginfo-8.7\]/g' /etc/yum.repos.d/almalinux-8.7.repo
sudo sed -i 's/\[appstream-debuginfo\]/\[appstream-debuginfo-8.7\]/g' /etc/yum.repos.d/almalinux-8.7.repo
sudo sed -i 's/\[extras-debuginfo\]/\[extras-debuginfo-8.7\]/g' /etc/yum.repos.d/almalinux-8.7.repo