B.1.5.RS:4.5 - Adopt or retain alternatives

Choose at the supported scope, accounting for adaptation, learning, operation and maintenance costs. Retain separate variants when their different strengths justify the burden; a single universal replacement is not required.

For an ongoing operation, use its ordinary rules for introducing change and retaining continuity. State the condition that would require reconsideration: changed inputs, another receiving whole, a tighter timing limit, lost support or a newly relevant result property. No separate certificate or trial is required merely to record that an existing basis was sufficient.

Return the decision in the form its receiver needs. Where the conclusion is only recognition of a plausible substitute, say so. A claim of guaranteed preservation needs the argument or assurance appropriate to that claim under B.3; a local decision under uncertainty uses C.11 and C.11.DUA.