Unable to Expand or Collapse Epics on Project Timeline

[Jacqueline Grace Padilla]

I recently lost the ability to expand and collapse epics on my project timeline to view the linked stories underneath. The only options currently available are to expand the column width or get a temporary preview of the hierarchy.

I can still see this functionality on some boards, but it appears to be unavailable or not configurable on others. Has there been a recent change to this feature, or is there a setting I may be missing? 

[Gor Greyan]

Hi @Jacqueline Grace Padilla

Welcome to the Atlassian Community!

You can see this post, where @Trudy P Claspill and @Arkadiusz Wroblewski introduced another article, where a similar experience arose.

https://community.atlassian.com/forums/Jira-questions/Timeline-not-grouping-child-items-to-Epics/qaq-p/3254332#M1184164

[Darryl Lee]

Right, as @Gor pointed to, this is unfortunately due to an update to the Timeline UI as detailed here:

• Upcoming: Unified, More Powerful Timeline for Jira Software Spaces

The good news is, YOU CAN OPT OUT. As the author wrote in an update yesterday (Jul 1, 2026):

If you'd like to opt out of the new timeline while we work through these gaps, please contact support to opt out.

I just wanted to add here that if this change adversely affects you, your site, and your users, you definitely should:

1. File a Support Ticket to opt out
2. Add a comment to the official thread for this change:
   Upcoming: Unified, More Powerful Timeline for Jira Software Spaces
3. Vote for JRACLOUD-98720 - Software Timeline: Hierarchy and epic grouping behaviour regression when filter is active 

Doing these things should send a signal to Atlassian that they need to prioritize this fix.