| Your position | Do this next | Evidence needed to move forward |
|---|---|---|
| Stakeholders disagree about the problem | Complete Gate 1: scope and ownership | An approved first-release charter |
| Scope is clear, but data or integrations are uncertain | Complete Gate 2: readiness | A sample migration, dependency register and remediation backlog |
| Several platforms appear suitable | Complete Gate 3: proof | Comparable results from buyer-defined scenarios |
| A preferred supplier has emerged | Complete Gate 4: commercial commitment | Normalised three-year cost, delivery responsibilities and exit provisions |
| Contracts are signed | Complete Gate 5: acceptance and operation; reopen any unproven earlier gates | Reconciled data, passed acceptance tests and a functioning support model |
| An incumbent renewal is approaching | Start the renewal and exit work in parallel immediately | Verified notice dates, export capability and a feasible transition calendar |
Keep retain, repair, extend, build and buy available as options. Use the same workflow and operating-cost tests to compare them. Do not assume that replacement is the objective.