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Click on User Groups adjacent to Manage Users
Click on Create Group to create groups for the project
Enter the Group name, select the users, and click the ADD and CREATE button at the bottom-right of the page.
Enable Group based allocation
To Enable or Disable group-based allocation from Advanced settings.
a. Click on Advanced and click on Project Task adjacent to Project Field.
b. Choose Choose Allocation Type as Group based.
c. Select Grouping Levels. If not selected, it will be applicable for all levels.
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d. Group-based allocation distributes tasks until L1 and L2 have completed execution. L3 will then receive tasks usually after submitting from L2within the groups only for selected levels. In this case, L3 will continue to receive tasks from different groups.