The thread installs Credit Suisse's AT1 write-down as a case in which going-concern notes can be cancelled on extraordinary government support while residual equity is swapped for value, because the deal was run as a commercial merger with a liquidity backstop rather than as a resolution that would have used the insolvency waterfall. The unresolved question is which repair, required before the 19 March ordinance, would have kept those notes from going to zero while the shares kept CHF 3 billion. Making AT1s convert into equity instead of writing to zero is one rule: that is what UBS's later AT1s do. Writing them down only inside a resolution, after equity is used, is a different first rule: that is the SRB, EBA and ECB Banking Supervision statement of 20 March 2023. Treating a federal default guarantee on liquidity loans as not a viability event is a third: that is the Federal Administrative Court's later reading of the same prospectuses, still on appeal. Those are not substitutes. Conversion with the viability event still tied to a liquidity line still lets a Sunday ordinance recapitalise the buyer by cancelling the notes. An EU-style hierarchy with the notes still written down outside resolution still lets a "commercial transaction" invert the stack. A tighter reading of "extraordinary support" with the notes still cancellable before equity still leaves the transfer BIS named. FINMA's two March releases, AS 2023 136 Article 5a, the Credit Suisse ad-hoc, and FSI Brief 21 already record the write-down, the residual equity, and the two legal bases. They do not say which one, required when the AT1s were sold, would have kept a state-backed liquidity line from becoming a CHF 16 billion transfer to the shares.