Issue Summary

Since ~June 12, automation rules sending emails to large groups (>250 members) only deliver to a small subset of users. The audit log incorrectly reports "Success."

Steps to Reproduce

1. Ensure you have an Atlassian group with more than 250 active users (e.g., the customer's group had 332 members).
2. Create a Jira Automation rule (e.g., triggered by "Issue Created").
3. Add a "Send customized email" action.
   Set the recipient to the large group identified in Step 1.
4. Perform the action that triggers the automation (e.g., create a new ticket of the specified type).
   • Verify Audit Logs: Observe that the Automation Audit Log marks the execution as "Success."

Expected Results

When a Jira Automation rule is configured with a "Send customized email" action targeting a group, the email should be successfully delivered to all active members of that group, regardless of the group size.

Actual Results

For groups with more than 250 members, the email is only delivered to a small subset of the group (often only the "overflow" users beyond the first 250).

Workaround

Currently there is no known workaround for this behavior. A workaround will be added here when available