# Changelog 2026 09 21

## Bug Fixes & Improvements

- **`opik import` can import traces of any age again** — The trace importer derived each imported trace's ID from the exported trace's `start_time`, which bakes that original timestamp into the ID's UUIDv7 prefix. Opik validates that an ingested ID's embedded timestamp falls inside an ingestion window around now — 24 hours by default on Opik Cloud, which is what keeps its storage layer partitioned correctly — so importing anything older failed with `Invalid UUID for id ... reason 'too_old'`. Imported traces now get IDs minted at import time, which also keeps IDs unique across projects and workspaces. `start_time` and `end_time` still carry the original values, spans and feedback scores are remapped onto the new IDs, and each trace records the ID it came from in its metadata as `_import_id`. Traces are imported in the order the source project listed them, so the destination trace list and thread view keep that order; note that the time-bucketed project metrics key off the ID, so imported traces count at import time. If you hit the error above, upgrade the SDK. See [Imported trace and span IDs](https://www.comet.com/tracing/advanced/export-data#imported-trace-and-span-ids).

## Related pages

- [Changelog 2026 09 14](./getting-started-changelog-2026-09-14.md)
- [Changelog 2026 09 07](./getting-started-changelog-2026-09-07.md)
- [Changelog 2026 08 31](./getting-started-changelog-2026-08-31.md)
- [Changelog 2026 08 24](./getting-started-changelog-2026-08-24.md)
- [Changelog 2026 08 17](./getting-started-changelog-2026-08-17.md)
- [Changelog 2026 08 10](./getting-started-changelog-2026-08-10.md)
- [Changelog 2026 07 20](./getting-started-changelog-2026-07-20.md)
- [Changelog 2026 07 13](./getting-started-changelog-2026-07-13.md)
- [Changelog 2026 07 06](./getting-started-changelog-2026-07-06.md)
- [Changelog 2026 06 23](./getting-started-changelog-2026-06-23.md)

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