The Fix
pip install celery==4.4.0rc5
Based on closed celery/celery issue #5113 · PR/commit linked
Production note: Most teams hit this during upgrades or environment changes. Roll out with a canary and smoke critical endpoints (health, OpenAPI/docs) before 100%.
@@ -10,6 +10,7 @@
import time
import traceback
+from calendar import timegm
from collections import namedtuple
from functools import total_ordering
Option A — Upgrade to fixed release\npip install celery==4.4.0rc5\nWhen NOT to use: Do not use this fix if the application does not require UTC timestamp handling.\n\n
Why This Fix Works in Production
- Trigger: Django-celery-beat schedules failed to work correctly due to timezone issues.
- Mechanism: The method used timetuple instead of utctimetuple, causing incorrect UTC timestamp handling
- Why the fix works: Fixes the issue by replacing the use of timetuple with utctimetuple in the Scheduler._when method to ensure correct UTC timestamp handling. (first fixed release: 4.4.0rc5).
- If left unfixed, the same config can fail only in production (env differences), causing startup failures or partial feature outages.
Why This Breaks in Prod
- Shows up under Python 2.7 in real deployments (not just unit tests).
- The method used timetuple instead of utctimetuple, causing incorrect UTC timestamp handling
- Production symptom (often without a traceback): Django-celery-beat schedules failed to work correctly due to timezone issues.
Proof / Evidence
- GitHub issue: #5113
- Fix PR: https://github.com/celery/celery/pull/5114
- First fixed release: 4.4.0rc5
- Reproduced locally: No (not executed)
- Last verified: 2026-02-09
- Confidence: 0.85
- Did this fix it?: Yes (upstream fix exists)
- Own content ratio: 0.83
Discussion
High-signal excerpts from the issue thread (symptoms, repros, edge-cases).
“## Steps to reproduce **https://github.com/celery/celery/blob/master/celery/beat.py#L261** What about the as_now timezone??? ## Expected behavior like this? But timestamp not support for python2.7? Or, tell me why wirte like this. This prob”
Failure Signature (Search String)
- Django-celery-beat schedules failed to work correctly due to timezone issues.
Copy-friendly signature
Failure Signature
-----------------
Django-celery-beat schedules failed to work correctly due to timezone issues.
Error Message
Signature-only (no traceback captured)
Error Message
-------------
Django-celery-beat schedules failed to work correctly due to timezone issues.
Environment
- Python: 2.7
What Broke
Django-celery-beat schedules failed to work correctly due to timezone issues.
Why It Broke
The method used timetuple instead of utctimetuple, causing incorrect UTC timestamp handling
Fix Options (Details)
Option A — Upgrade to fixed release Safe default (recommended)
pip install celery==4.4.0rc5
Use when you can deploy the upstream fix. It is usually lower-risk than long-lived workarounds.
Fix reference: https://github.com/celery/celery/pull/5114
First fixed release: 4.4.0rc5
Last verified: 2026-02-09. Validate in your environment.
When NOT to Use This Fix
- Do not use this fix if the application does not require UTC timestamp handling.
Did This Fix Work in Your Case?
Quick signal helps us prioritize which fixes to verify and improve.
Prevention
- Capture the exact failing error string in logs and tests so you can reproduce via a minimal script.
- Pin production dependencies and upgrade only with a reproducible test that hits the failing path.
Version Compatibility Table
| Version | Status |
|---|---|
| 4.4.0rc5 | Fixed |
Related Issues
No related fixes found.
Sources
We don’t republish the full GitHub discussion text. Use the links above for context.