BlockBeats report, on April 15, Bitcoin contributor Jameson Lopp and other cryptographers proposed an initiative that could force Bitcoin holders to migrate their tokens to new quantum-resistant addresses, or their tokens will be permanently frozen by the network itself. Under this scenario, holders would technically still "own" the coins but would lose the ability to transfer them.
This is known as Bitcoin Improvement Proposal BIP-361 and was updated on Tuesday in Bitcoin's official proposal repository under the title "Post-Quantum Migration and Legacy Signature Deprecation."
BIP-361 builds upon the BIP-360 proposal introduced in February. BIP-360 introduced a soft fork—a type of network upgrade—aimed at enabling a new transaction type called "Pay-to-Merkle-Root" (P2MR). This approach draws from Bitcoin’s Taproot (P2TR) framework but removes key-based spending paths, thereby eliminating an element widely regarded as vulnerable in the quantum era.
BIP-361 proposes dividing the migration into three phases. Phase A begins three years after activation, prohibiting anyone from sending new bitcoins to legacy addresses vulnerable to quantum attacks. You can still spend from these addresses, but you cannot receive any coins.
Stage B will activate five years after activation, rendering legacy signatures (ECDSA and Schnorr) completely obsolete; the network will reject any attempt to spend coins from wallets vulnerable to quantum attacks. Essentially, your coins will be frozen.
Finally, Stage C is a rescue solution still under research: holders of frozen wallets may be able to prove ownership through zero-knowledge proofs—a method of demonstrating knowledge of a secret without revealing the secret itself. If successful, the coins frozen in Stage B could be recovered.