Change Task and Subtask due date based on Epic due date change through automation

Question

I am looking to change the due date of all tasks and subtasks of a given Epic when the due date of the epic is updated.

This works using automation but not exactly the way I need it to

For example using:

* When values change for due date
* Issue type = Epic
* Branch: For stories
* Then edit issue fields due date

BUT the piece that is missing is how to change the due date from the original task/subtask ticket due date to however many days the Epic bumps out.

For example: Original Epic Due Date is August 20, 2021, new updated due date is August 30, 2021

* Task Original Due date is August 22, 2021
* Subtask Due date is August 21, 2021

What smart field can be used to update the current due date for task/subtask to the number of days the Epic has been updated by (10 days)

FR Jira Dev · Answer

Thanks I will take a look at trying this.  This seems like a desired feature and would be very helpful for teams

Bill Sheboy · Answer

Hi @FR Jira Dev

First thing, you probably will want to perform a cascading change like this with two rules:

* epic change leads to updating the story/task/bug children
* story/task/bug change leads to updating the sub-tasks.  For this rule, ensure to set the option in the details for "Allow Rule Trigger", as this allows rule #1 to fire off rule #2

Next, to figure out the delta-days from the epic you may use the changelog (from/to), which you can learn about here: https://support.atlassian.com/jira-software-cloud/docs/smart-values-general/#Smartvaluesgeneral---changelog--

This would be much easier if this delta value could be calculated and saved for reuse (e.g. created variables).  But that will not work, so you will need to use the delta directly in the field edit for children.  (The problem is created variables cannot be used as function parameters.)

As the math part may be tricky, I suggest writing intermediate results to the audit log and to build/test your rule incrementally.

Best regards,
Bill

Trudy P Claspill · Answer

Hello @FR Jira Dev

It looks as though you did not complete the entry for your post, as the last sentence has ended abruptly in the middle. Can you complete your post so we know where you are asking for help?