In the Amortization & Accretion Rules panels, you can specify a value for the the Use Third Party Cash Flows (tag 11768) field.
In the amortization rule, if you set the Use Third Party Cash Flows field (tag 11768) to Yes, the Earnings process uses the third party cash flows in the Vendor Cash Flow table if there are cash flow records available. If you set the Use Third Party Cash Flows field to No, the Earnings process does not use third party cash flows. When the amortization rule specifies use of third party cash flows, this election overrides any other cash flow assumption such as calls, puts, prepayment model, and speeds, and tells the Earnings process to use those cash flows for the purposes of deriving an amortization yield.
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