I want to have an automation that allows the user who has a task to do in the far future to use the manual automation option to input a desired due date in the future. This value will then be entered in the Due Date field. As the due date is approaching, the automation should send a reminder email and assign the ticket to the user who triggered the event.
FYI: I chose the manual trigger option because I do not want this to happen everytime the due date is changed, just in selected situations.

Problem with the proposed solution:
the smart values condition does not work as intended. Essentially I want that 3 days before the due date then the email and ticket assignment will be executed. (for reference I read about the smart values for date and time here:
https://support.atlassian.com/cloud-automation/docs/jira-smart-values-date-and-time/ )
but using smart values in this way means that the condition needs to be evaluated not just at the time of the automation execution but until the condition is met --> how to do this?
I am open to feedback on implementing the use case in a better way or any improvements to my proposed solution.
Thanks very much in advance!