AT:

• performs a transition from "SUSPENDED" state into "ACTIVE" state
• The resume of a
  • Stage must be propagated to all its contained child instances
  • HumanTask must activate the instantiated UserTask
  • ProcessTask has no effect on the called ProcessInstance
  • CaseTask has no effect on the called CaseInstance

Note:
If a CaseTask or ProcessTask is suspended and if the called sub instance (case instance or process instance) has been completed in the meantime, then the CaseTask or ProcessTask should be able to complete after resuming. And if the sub instance has not been completed, then the CaseTask or ProcessTask should not be able to complete.