In 12.6. Installing a primary control plane node on a healthy cluster and 12.7 Installing a primary control plane node on an unhealthy cluster, in Prerequisites section:

For "You have installed a healthy cluster with a minimum of three nodes", please change link to https://access.redhat.com/documentation/en-us/assisted_installer_for_openshift_container_platform/2024/html/installing_openshift_container_platform_with_the_assisted_installer/installing-on-prem-assisted.

For "You have assigned role: master to a single node", please change link to

https://access.redhat.com/documentation/en-us/assisted_installer_for_openshift_container_platform/2024/html/installing_openshift_container_platform_with_the_assisted_installer/assembly_role-assignment

When you're done, you'll have fixed 4 links. Please let me know if you have questions.