Issue Summary

In Team-Managed Projects (TMP), when attempting to filter issues on the Timeline view by Label, any label that is exclusively applied to an Epic (or parent hierarchy level) does not appear in the filter dropdown list, and searching/typing the label name returns no results.

However, if the exact same label is added to at least one standard work item (e.g., Story, Task, Bug) on the board, the label immediately becomes available and searchable in the Timeline filter dropdown.

Steps to Reproduce

1. In a Jira Cloud Team-Managed Project, navigate to the Timeline view.

1. Create or select an Epic and add a unique label (e.g., test-epic-only). Ensure this label is not present on any standard issue (Story/Task/Bug).

1. On the Timeline page, click Filters > select Label.

1. Browse the dropdown or type test-epic-only into the search box.

Expected Results

The label test-epic-only appears in the dropdown list and can be selected to filter the Timeline view.

Actual Results

• The label test-epic-only is omitted from the dropdown list.

• Manually typing the label name returns "No results found", preventing users from filtering the Timeline by that label.

Workaround

Add the affected label to at least one standard work item (Story, Task, or Bug) in the project. Once present on a base issue type within the board scope, the label will appear in the Timeline filter dropdown and filter Epics/child issues as expected.