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By default the Resource Load Chart (RLC) displays all resources irrespective of whether they are assigned or unassigned to tasks or not. This helps you quickly identify free resources to allocate to incoming work items. You can also use sophisticated filters such as Resource : Workspace or Resource : Search to narrow down on specific resources by workspace or specific keywords.
If you wish to explicitly see the Free hours for a resource, you can edit the RLC report by clicking on its three-line menu icon and 
and add the Free (Est) column from the View Tab. Alternately, you can also view the Resource Load Chart (Real-time) report. This report provides visibility of free resources in real-time & helps the PM adjust allocations to ensure optimal resource utilization.
If a task is completed before schedule, will the resources be freed?
Celoxis does not automatically free up any resources. However, you can use the RLC to show all resources in the given time period you require, who are working on assigned to tasks that have a Task Status as Completed
Completed (Task : Schedule Status filter: Completed). This will show all resources and their allocations on tasks in that period that are already completed. Since these tasks are already completed, the allocated hours against those tasks are potentially free. Then, you can assign those resources to other tasks.
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If a project is put on hold, will the resources be freed?
Once again, Celoxis does not automatically free up any resources. However, you can filter the RLC to show all resources in the given time period you require, who are working on tasks in projects that are in the On Hold (Project : Phase : On Hold). Since you know that project is on hold, potentially all that allocation you see on the chart is freed up and you can choose to assign those resources to your tasks.
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