Automation: Unable to add parent or epic to created issue

I'm experiencing what appears to be a regression with the new Create work item automation action after the Epic Link → Parent migration.

My use case

I have a scheduled Automation rule that creates multiple Task work items. Each Task should be created under a specific, existing Epic (for example, GMR-155).

This automation worked before July. The issues only started after the recent Epic Link → Parent changes in Jira Cloud.

What I'm seeing

When configuring the Create work item action:

• The Parent field does not allow me to select an issue like the Epic field. (Epic field is now blocking automated tickets from being created.)
• Instead, the Parent field only allows selecting:
  • Work item
  • Trigger work item
• I've also tested using the Parent Field by simply typing in GMR-155, and that did not work. 

Because this is a Scheduled rule, there is no trigger work item, so neither option is usable.

Additional testing

I've tried several approaches:

• Creating the Task without a Parent → Works successfully
• Setting the Parent field → Fails
• Using the legacy Epic Link field instead → Also fails
• Adding a branch to edit the created Work Item to add the Epic or Parent. → Both options fail.
• Using Additional Fields JSON:

{
  "fields": {
    "parent": {
      "key": "GMR-155"    }
  }
}

→ Also fails.

The Epic exists, is in the same project, and the created issue type is a standard Task, so the hierarchy is valid (Epic → Task).

I've also recreated the Create work item action from scratch to rule out a corrupted automation configuration, but the behavior is the same.

Why I think this may be a regression

From what I can tell:

• Removing Parent/Epic Link allows the automation to complete successfully.
• Adding either Parent or Epic Link causes the Create action to fail.
• The Parent UI no longer behaves like the previous Epic picker and appears to only support automation-context work items.

Questions

• Is anyone else seeing this behavior with the new Create work item action?
• Has the expected configuration changed following the Epic Link → Parent migration?

I found this previous Community thread, but the accepted solution does not appear to resolve the issue anymore in my Jira Cloud instance, so I'm wondering if there has been a recent regression or behavior change since that discussion.

https://community.atlassian.com/forums/Jira-questions/Automation-Unable-to-add-Parent-to-created-issue/qaq-p/3017814