CDN-200 closes the D9 frozen-switch ledger. CDN-195 froze the operator switch, CDN-196 mapped and preregistered the crossing, CDN-197 and CDN-198 passed two above-crossing asymptotic-floor holdouts, and CDN-199 supplied the response-kernel crossing equation. Closure applies to the frozen source/phase-gradient switch and its CDN-179-style asymptotic-floor observable, not to a universal selector claim.
Nicky Joseph Hubertus Catharina Hacquier (Fri,) studied this question.