Page Comparison

This article explains a step by step This article contains instructions on how to copy the value of the next due date Next Due Date custom field into the due date Due Date field by using COT the Create on Transition app.

Instructions

The following is the custom field called "screenshot contains sample data that must be copied to Due Date:

Image Added

Here, next due date"( is a custom field type is a date) and its Date field whose value is set to 18/DevDec/19. Image Removed
Update the Use a post function to copy the "next due date" value into due date customfield by following the below steps.
 
  
You need to use the substitution variable to copy the value from the next due date to the due date field. In the post function, you need Set the Due Date field to %original_customfield_10300%. 10300 is nothing but the Id of the custom field "next due date".Follow the below steps to 

customer requirement is like if he does the transitions he wants the value of the next due date field to be copied into the due date field. This can be achieved by giving the custom field id of next due date i.e %original_customfield_11602% in the post functions. copy the %original_customfield_11602% into the following location
go to workflow--> edit the transition --> fields --> due date

...

this value on transition.

Use the following instructions to know the ID of the custom field whose value is to be copied:

1. Log in as an administrator in your Jira instance.

2. Select Cog menu (Image Added) > Issues.
   Image Added   

3. Select Issues from the top menu bar and click Custom Fields.
   Image Added
   

4. Search for the next due date custom field, select Cog menu (Image Added) > Configure.
   Image Added  

5. Anchor
   customFieldID customFieldID

   Custom field ID is shown as customFieldId in the URL. Note just this parameter and value pair as shown:
   Image Added

Use the following instructions to update the post function in a workflow and copy the custom field value into the Due date field:

1. Log in as an administrator into your Jira instance.
2. Select Projects from menu bar and click the project name. If the project is not visible from the drop-down, click View all projects, and, select the relevant project.
3. Click Project settings on the Project page to administer the project.
4. Go to the Workflows section and edit the relevant workflow scheme.
   Image Added
5.  Click the transition with the post function to be updated. As an example, update the Done post function.
   Image Added
6. Click Post Functions, and then, click the pencil icon to edit the function.
   Image Added

7. Click Detailed Fields. Enter the substitution variable, %original_customfield_10300%, in the Due date field. Note that this custom field ID was copied from the URL from step 5 in the previous section.
   Image Added

8. Publish the Workflow and perform the Done Transition in the Jira issue. 

Thus, when you click Done in the Jira issue, the value of the custom field, next due date, is copied to the required, Due date, field in the corresponding issue.