Date fields in parent and subtasks - how to automate

[Richard Vencu]

Let say I need to automatically update the Due Date of a parent issue as MAX (list of Due Dates of all subtasks)

Besides I could not find a way to iterate through all Due Date values of subtasks I got an other issue while I was trying to maintain Due Date at every change of the subtask field by comparing the parent issue Due Date with fieldChange.to date, If the parent Due Date is empty I was unable to perform any MAX, or isBefore or anything like this. I even tried things like IF(issue."Due Date" is empty then copy subtaks due date else compare and select minimim value) but I always end with an error.

For instance I know of this syntax {{^issue."Due Date"}}some default{{/}} but how to apply it to this {{fieldChange.to.isBefore(issue."Due Date")}} ?

However even trying this logic would succeed it does not protect from the event of setting up a date to a subtask, copying that date to the parent then changing all dates from subtasks to an earlier date. The parent date would remain at the latest date ever set. A way to iterate through subtasks and compare all their date fields seems necessary,

Maybe this is an unsolvable problem with current automation capabilities but if someone has any idea that can help solving it I would appreciate the input.