When an analyst is unavailable, common practice is to set 'Available' field on contact detail page to NO/unchecked. However, it still allows you to transfer or assign a CA Service Desk Manager (CA SDM) request to the unavailable analyst. Are unavailable analysts supposed to display in the list?
The contact detail 'Available' field is related to CA SDM Auto Assignment. It is the same available field in the group detail page member tab for each group member.
The field is used for auto assignment. A manual transfer or assignment through the user interface allows you to select contacts that are "Unavailable". However, auto-assignment will use the available field to determine whether tickets are auto-assigned to contacts.
CA Service Desk Manager 12.9 Administrator Guide - How to Implement Auto Assignment
CA Service Management 14.1 - Auto Assignment