This sounds like a deadline or an escalation. Would either of those suit your purpose? After three days the task deadlines and moves to the next step or it remains on the same step but escalates to another user.
Hi Robert, is deadline, but after 3 days, the taskdoes not scale to another user or task should be removed from the workspace.
Place 3-day deadline, but the task remains in the workspace after completing the period, how could I remove it?
True, when a task deadlines a notification (deadlined task) remains in the user's To Do list. However the only thing that user can do with that notification item is to remove it. It remains there to notify the user that the task has deadlined and moved on. The owner of that notification is the only one who can remove it. The task itself has moved on to where ever your process sends it.