Ledger CTO Charles Guillemet says Bitcoin faces a migration challenge, not an immediate quantum crisis.SHRINCS combines stateful signatures with a stateless fallback while relying on SHA-256 for security today.Current SHRINCS signatures range from 548 bytes to 5,777 bytes, depending on the signing path.Reusing one stateful signing slot can enable forged signatures, creating serious wallet-level fund theft risks.Bitcoin BIPs 360 and 361 remain drafts, leaving post-quantum migration policy unresolved across the network.