QUB Core v1.7.7 HF120 - Protocol Epoch 2

QUB Core v1.7.7 HF120

HF120 is a mandatory forward-only QUB mainnet protocol upgrade.

Activation height: #24000.

This release introduces Protocol Epoch 2 with a block-version gate. From block #24000 onward, official upgraded QUB mainnet nodes require block version 2. Old/custom miners that keep mining block version 1 after activation will be on a fork rejected by upgraded official nodes.

What changed

• Adds Protocol Epoch 2 activation at mainnet block #24000.
• Requires block version 2 at and after #24000.
• Builds solo and pool block templates with the correct expected block version for the next height.
• Adds CLI info and preflight visibility for Protocol Epoch 2.
• Keeps HF117 mempool/reorg tx recovery and wallet-pending-txs.json.
• Keeps HF118 QUB Melt / JIN Infuse GUI enablement.
• Keeps HF119 non-blocking QUB/JIN preview/signing and public-GUI winner brake.

What did not change

• No DAA change.
• No checkpoint change.
• No genesis/economics change.
• JIN Coin -> JIN Token conversion remains disabled until bridge release.

Operator note

Seeds/direct nodes/explorer infrastructure should be upgraded before #24000 so the official network is already serving and enforcing Protocol Epoch 2 at activation.