"checking the Publish instance(s) attached to the Dispatcher associated to the impacted data center can help identify if there are any replication or caching issues that prevent the latest page content from being served"

Advise the customer to use Launches . According to Adobe Experience Manager documentation1, launches in AEM Sites provide a way to create, author, and review web site content for future release. Launches can also be synchronized with the production web site and activated at a scheduled time1

According to Adobe Experience Manager documentation1, the Adaptive Image Servlet is a feature that automatically selects the most appropriate rendition of an image asset based on the size of the container in which it is displayed. This can reduce the number of renditions needed and improve performance and scalability of AEM DAM. Caching image variations in Dispatcher can also help reduce repository growth and network traffic. Reimplementing article-related components to use AJAX can prevent stale content issues by dynamically loading fresh content from AEM without refreshing the whole page.

"if a user is removed from an LDAP group that has been synchronized with AEM, then that user will be removed from all AEM groups that they are a member of".

According to Adobe Experience Manager documentation1, a publish (preview) server is a publish instance that is used for previewing content before it goes live on the production server. This can be useful for verifying content with third-party vendors or other stakeholders who need restricted access.