CUST.8:4.3 - Construct alternatives that preserve a complete receiving result
| Change form | Construct the continuation | Boundary to settle |
|---|---|---|
| Compatible extension | Preserve supported old use while making a new variation obtainable. | Whether defaults, meanings, support and resource demand remain compatible. |
| Supported profile or coexistence | Keep distinct old and new conditions explicit and provide both for an attainable period. | Who maintains each path and which combinations can operate together. |
| Adapter or conversion | Supply a qualified translation or transformation with its acceptance and exception handling. | Lost information, changed effects, partial failure and continuing maintenance. |
| Explicit migration | Supply the receiving provision and the work by which each selected use reaches it. | Preparation, participation, authority, recovery and the point at which old provision can end. |
| Separate offering | Give materially different results their own supportable provision rather than force them into one family. | Shared contributions can remain shared without promising interchangeability. |
| Retained arrangement or no change | Continue the supported local or common provision within its actual conditions. | Its remaining burden and any later condition that makes continuation untenable. |
Build the receiving path before scheduling its adoption. Name the new result, preparation, available means, actual performers and assistance. Work backward to the old dependencies that remain necessary until that result is obtainable. If a required conversion, explanation or support contribution is missing, construct or obtain it; a migration date does not fill that gap.
For an engineered platform migration or retirement, use the complete SYSE.29 — Decide Whether and How to Migrate or Retire a Supported Platform Path. It supplies affected-use recovery, transition alternatives, an executable increment, receiving-use and failure checks, and explicit retirement scope. Bring its qualified technical transition into the wider customer arrangement. CUST retains the family choice, promise alignment and resource decision; it does not replace that engineering treatment.