# Stage 9: How do you rehearse migration and prove acceptance?

**Run a repeatable migration rehearsal with documented reconciliation before production cutover.**

Supplier investment does not remove the buyer’s responsibility to verify the result. On **29 June 2026**, Accenture and ServiceNow announced an AI-powered migration offering alongside managed security services. The announcement establishes the offering, not an independently validated duration, price or accuracy for your migration. ([newsroom.accenture.com](https://newsroom.accenture.com/news/2026/servicenow-and-accenture-launch-ai-powered-services-to-accelerate-the-shift-from-legacy-risk-platforms-to-agentic-ai))

### What is the proposed rehearsal sequence?

1. Freeze and identify the source extract.
2. Run approved cleansing and transformation steps.
3. Load reference data and parent objects in the required order.
4. Load dependent records and relationships.
5. Transfer or register evidence and history using approved methods.
6. Capture rejected rows and exceptions.
7. Reconcile objects, relationships, dates and files.
8. Run business, permission and reporting tests.
9. Correct defects and repeat with the same controlled process.
10. Rehearse the final delta and cutover sequence.

### What should reconciliation prove?

For each source population, account for:

**Extracted records = migrated records + approved archival/exclusion dispositions + unresolved exceptions.**

Where records are merged or split, use a source-to-target crosswalk rather than expecting equal counts. A successful row count is not enough.

Recommended checks include:

- Source IDs can be traced to target IDs or approved dispositions.
- Critical relationships resolve correctly.
- Owners and permissions match the approved design.
- Required dates and assessment periods retain their meaning.
- Files are retrievable and linked correctly; use checksums where files should remain unchanged.
- Historical material is labelled as historical, not recreated as a new approval.
- Reports reconcile to the agreed test population.
- Rejected records are visible and assigned.

### What should block go-live?

Set severity definitions in advance. Suggested blockers are:

- An unresolved sensitive-data permission failure.
- Missing critical records or evidence without an approved disposition.
- A mandatory workflow that cannot complete.
- Unexplained reporting discrepancies in the agreed scope.
- No workable cutover or recovery procedure.
- No accepted operating owner or support route.

Do not replace these gates with a single percentage of test cases passed. One failed critical permission test can matter more than many successful cosmetic tests.

**Exit gate:** signed migration reconciliation, business acceptance, security acceptance and documented treatment of remaining noncritical defects.