An order freezes its checkout policy at placement
Context
Administrators can change checkout configuration after a purchase was placed.
Decision
Capture the governing policy at placement and use the recorded processing rules for that sale. Migrated records retain the implemented live-policy fallback.
Alternatives Considered
Using current policy for every step changes existing agreements. Splitting mixed carts into several sales is a separate unimplemented scope decision.
Consequences
New policy edits govern future placements. Reports retain how the chosen policy was resolved, and migrated-order handling requires its own caveat.