Time Duration as an expression

Need help to satisfy the following condition :

an email reminder needs to be sent one day before due date. I am setting the due date a human task.
The next task has a boundary timer event.
What can I use as expression for timeDuration?

Anything like ‘PT’ + ({duedate} - {now} - 246060)/1000 + ‘S’

For the timeDuration you can use ISO 8601 Durations or you can use java.time.Duration.

For what you described if duedate and now give you back java.util.Date you can’t subtract like you are doing now.

Just FYI you can also use a defined date if you want as well for the timer event.