Improved migration guide

doc/user/infrastructure/clusters/migrate_to_gitlab_agent.md

@@ -70,7 +70,11 @@ Follow the process for the [CI/CD workflow](../../clusters/agent/ci_cd_tunnel.md
 
 ## Migrate from GitLab Managed applications
 
-Follow the process to [migrate from GitLab Managed Apps to the cluster management project](../../clusters/migrating_from_gma_to_project_template.md).
+[GitLab Managed Apps (GMA)](../../clusters/applications.md#gitlab-managed-apps-deprecated) were deprecated in GitLab 14.0, and
+the agent for Kubernetes does not support them. To migrate from GMA to the agent, go through the following steps:
+
+1. [Migrate from GitLab Managed Apps to a cluster management project](../../clusters/migrating_from_gma_to_project_template.md).
+1. [Migrate the cluster management project to use the agent](../../clusters/management_project_template.md).
 
 ## Migrate a cluster management project