Additional information supporting references for Tax Journal

Summary: Additional information to be captured as supporting reference for tax journal (FBDI)

Content (please ensure you mask any confidential information): We have integration to load tax journals using FBDI. At the same time, we need to capture additional information like contract number which is dynamic in nature as additional information. I did not find DFF in Tax journal fbdi whereas I can see EFF (Extensible Flex fields). Is it possible to use EFF for tax journal. If so request, you to share some reference document

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