[bug]: "Updated At" filter with "IS" operator returns no results on self-hosted instance

Is there an existing issue for this?

• I have searched the existing issues

Current behavior

What I do:
I filter work items by Updated At → IS → today/yesterday/tomorrow on a self-hosted Plane instance (v1.3.1). We have work items that were updated today.

What I expect:
I expect to see the updated work items in the results, but I get no results at all.
The same filter on the Plane demo instance works correctly. Browser dev tools show the identical API parameter updated_at__exact being sent in both cases.

Steps to reproduce

1. Open any project on a self-hosted Plane instance
2. Update any work item
3. Add filter: Updated At → is → today
4. Observe: no results returned, despite work items being updated today
5. Try "is" → yesterday → still no results
6. Try "is" → tomorrow → still no results
7. Same filter on demo.plane.so → works correctly

Environment

Deploy preview

Browser

Google Chrome

Variant

Self-hosted

Version

v1.3.1