Summary of Key Changes

Before

• Admin-only model: Contracts could only be migrated by their admin

• Binary upgradeability: Contracts were either upgradable (with admin) or not upgradable (without admin)

• No governance integration: No way for governance to control contract upgrades

After

• Hybrid model: Admin + governance control combinations

• Governance integration: On-chain proposals can authorize specific migrations

• One-way governance flag: Contracts can irreversibly require governance approval

• Four upgrade scenarios: Multiple combinations of admin and governance requirements

• Batch migrations: Single governance proposal can authorize multiple contract migrations

• Governance-only migration pattern: New mechanism for contracts with no admin but governance control

The schematics of the updated system is shown below: