Solana Draft Proposes Retiring Durable Nonces No Earlier Than May 2027

The significance here is less about a deprecation date than about the migration burden it places on custodians, whose offline-signing setups depend on durable nonces behaving predictably. Changing how failed pre-signed transactions are handled is the sharper edge: it touches the failure modes that custody and settlement workflows are built around, not just the signing step. The open question is whether the replacement programs' failure rules get settled well before the retirement window, since custodians need lead time to re-engineer flows that are rarely exercised until something goes wrong.