Business situation
The old system still holds unpaid allocations and unfinished refunds when the replacement goes live.
The key decision
Inventory orders, business calculations and provider results separately. Agree which system continues each unfinished item.
How implementation works
Retain original mappings, state snapshots and reconciliation reports. Deduplicate receipts and route unresolved items to authorized review.
Business value and evolution
Finance can explain continuity and each historical responsibility. New trading proceeds under new rules without hiding old discrepancies.