Bitcoin’s quantum-security debate is shifting from selecting a replacement signature scheme to the practical challenge of migrating wallets, hardware and existing funds. Ledger Chief Technology Officer Charles Guillemet said Bitcoin does not face an immediate quantum-computer crisis because no cryptographically relevant machine capable of breaking its current signatures is known to exist, but research, implementation and user adoption could take years. His analysis examined SHRINCS, an unfinished Bitcoin-specific post-quantum signature proposal that combines a compact stateful path with a larger stateless fallback. The draft uses SHA-256, targets approximately 128 bits of classical security and 64 bits of quantum security under its chosen parameters, and specifies a 48-byte public key. Current signatures range from 548 to 4,619 bytes on the stateful route and reach 5,777 bytes on the stateless path. Reusing a stateful signing slot could enable forged signatures and make funds stealable, while lost or uncertain signing state requires wallets to abandon the compact route and use the larger fallback. The design also creates challenges for backups, multi-device wallets, non-hardened BIP32 derivation, threshold signing and secure-hardware performance. SHRINCS remains an unnumbered draft whose formal security proof is unfinished and is not active on Bitcoin mainnet. BIP 360 and BIP 361, which address aspects of quantum exposure and migration, also remain Draft proposals. Governance questions include how to handle dormant or lost coins that are not moved before a future transition.