Difference between due dates of subtasks

[Douglas Oliveira]

What function do I use to make the due dates of two subtasks always ten days apart?

[Jack Brickey]

Well my answer would be to use automation. However I can’t suggest exactly how I would map that out without understanding more about your situation. Where does the Initial due date come from? Maybe you want to create two sub tasks when a parent task is created under certain conditions and the initial due date is in the parent task in which case I would set the first sub task based on the parent and the second subtest to be 10 days after the first. In any event have a look at the documentation on automation critically around dates and that should get you going. smart-values-date-and-time-functions 

[Douglas Oliveira]

Hello @Jack Brickey , Thanks for return.

I am using the automation, What I need is that whenever I change the parent event's due date, the subtasks change automatically, I can do that for a subtask, making it copy the parent's condition, but I can't make the others follow the process.

[Jack Brickey]

What do you mean by the others “follow the process“? Can you give an example showing the dates structure that you want. For example…

parent due : 8/15/21

• subtask 1 due = parent due + 10 = 8/25/21
• subtask 2 due = parent + 20 = …
• subtask 3 due = parent +30 = …

note I haven’t tried anything like this before and I suspect somehow you have to differentiate such as labels the sub tasks so that you know how much to add to the parent due date.

on the other hand if all subtasks should have the same due date as a parent and that should be a matter of just copying the due date and all sub tasks.

[Douglas Oliveira]

For example:

Parent start:  7/15/21

Parent due: 8/15/21

• subtask 1 due = parent start + 2 = 7/17/21
• subtask 2 due = parent start + 12 = 7/27/21
• subtask 3 due = parent start + 20 = 8/04/21
• subtask 4 due = parent due 

 This I already did.

But i want if i need to change the parent due date happens:

Parent start:  7/15/21

Parent due: 8/08/21

• subtask 1 due = parent start + 2 = 7/17/21
• subtask 2 due = parent start + 5 = 7/20/21
• subtask 3 due = parent start + 13 = 7/28/21
• subtask 4 due = parent due.

The subtask 1 don't need to change. 

[Jack Brickey]

So I’m not sure how to accomplish this TBH. I was looking for a pattern in your example but it doesn’t seem to exist. In other words if the subtask is always due X-days from the parent that would be a pattern. In any event I’m thinking you might need another date to record the previous due date to calculate the change in the parent date so as to leverage in the sub-task calculation. 

[Douglas Oliveira]

A pattern is the number of days between substasks, the time of subtask 3 and subtask 4 would be the same forever.