Stuck on 409 Conflict during bulk shift swap API updates

Stuck on a 409 Conflict error when pushing approved shift swaps via the /v2/wfm/schedules endpoint. The payload matches the schema, and the agents are available in the Chicago timezone, but the API rejects the request citing a scheduling conflict that doesn’t exist in the UI. We are using the Python SDK v3.2. Is there a hidden validation rule for overlapping availability windows during bulk operations?

Thanks for the help.