Bitcoin developers proposing quantum upgrade warn 25% of total BTC supply exposed to attack risk

Bitcoin developers are proposing an upgrade to protect the network from potential attacks by quantum computers. They estimate that about 25% of the total Bitcoin supply, held in older types of addresses, is vulnerable because their public keys are already exposed. The developers propose a three-phase plan to move users to newer, quantum-resistant address types. The first phase encourages users to send Bitcoin only to these new addresses, starting three years after a specific upgrade is implemented. The second phase would freeze older, vulnerable addresses roughly five years after the first phase begins. The final phase would offer a way for users who miss the migration window to recover their funds using advanced cryptographic techniques. Concerns have been raised that this could affect inactive Bitcoin wallets.