Milestone REGOPT: S1.b Produce reference opt-in design for a Spiral 1 project

Produce a reference design showing how a planned Spiral 1 project(s) opt‐in can be implemented with Spiral 1 end‐to‐end connections. Demonstrate how the design meets opt‐in requirements from the initial requirements document. Submit results to Opt-in, Control Framework, and OMIS working groups.