I can use some workflow context specific mvel function helpers for defining escaltion rule's condition

Those functions are:

Available on the context when evaluating conditions on transitions and escalation rules:

• WorkflowFn.timeSinceWorkflowWasStarted()
• WorkflowFn.timeSinceTaskWasStarted ()
• WorkflowFn.timeSinceDueDateIsOver()

Available on the context when evaluating conditions on escalation rules:

• WorkflowFn.timeSinceRuleHasBeenFalse ()
• WorkflowFn.ruleAlreadyExecuted()

They all return the number of miliseconds since the given event, compared to currentDate.

The do not require to set any particular node variable or so.