S3 Datalake staging folder date format changed from YYYY-MM-DD to MM-DD-YYYY for Node source only

[vedantp-genuin]

Environment: Self-hosted, rudder-server v1.4.0, rudder-transformer 1.117.1, auto-scaling setup.
Issue: After April 4, 2026, the staging folder date format for our Node source changed from YYYY-MM-DD to MM-DD-YYYY when writing to our S3 Datalake destination

Key facts:
Only affects the Node source (channel: server). Android, iOS, WebApp, and Python sources are unaffected.
No images, SDK versions, or destination settings were changed.
Both formats appeared on April 4 itself; after that date, only MM-DD-YYYY appears for the Node source.
analytics-node SDK version 1.1.5 unchanged.
library: rudderstack/rudder-sdk-node: 1.1.4

Question: Was there a destination definition or control plane schema change around April 4 that could affect how rudder-server v1.4.0 generates staging folder paths for server-channel sources?

[contributor-support]

Thanks for opening this issue! We'll get back to you shortly. If it is a bug, please make sure to add steps to reproduce the issue.

[achettyiitr]

Staging folder paths are decided based on whether we can list previous files. Can you check if you see any error logs of this kind for April 4th?

[achettyiitr]

It's config-driven as well. We can set BatchRouter.datePrefixOverride config as YYYY-MM-DD, but then it will be applicable for all staging files.

[contributor-support]

Thanks for opening this issue! We'll get back to you shortly. If it is a bug, please make sure to add steps to reproduce the issue.

[vedantp-genuin]

Thank you @achettyiitr and @saivarunr , after adding the below key in the env, we were able to dump files in warehouse-staging-area!

- RSERVER_BATCH_ROUTER_DATE_PREFIX_OVERRIDE=YYYY-MM-DD