Assignment Candidate is a user who is able to get the task (assign it to herself).
One task can have multiple Assignment Candidates but only one becomes assignee of the task.  

Assignment Candidate views the task in "Available tasks" list on Tasks screen.
Assignment Candidate can:

  • open available task
  •  view task description
  •  view data form
  •  write comments
  • change due date
  • assign/reassign the task 

But she cannot :

  • fill editable form fields,
  • complete the task
  • reopen completed task

till she becomes assignee for the task.
If Assignment Candidate assigns the task to herself, this task moves to "My tasks" list on Tasks screen ("Active" tasks filter should be used).

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