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HMRC internal manual

Compliance Operational Guidance

Alternative rights of recovery (PAYE directions): contract settlements: direction and decision made

You can still consider a contract settlement as a means of recovery after a direction and decision have been made, so long as those proceedings have not become final. They become final if no appeal was made within the time allowed, or any appeal made is determined.

When settlement is by contract any open appeal is not formally determined. Any unpaid amounts that are to be collected through the contract settlement must be informally discharged.