MAJOR UPGRADE WITH DOWNTIME ON MAINNET WEDNESDAY 10 DECEMBER 9 AM US EASTERN / 1400 UTC

1. #1Wayne Collier04-12-2025source ↗
   MainNet will go through a protocol-changing major upgrade on Wednesday, December 10th, starting at 9 am US Eastern (1400 UTC). Here are the most important things you need to know, and some recommendations on how to prepare.

   • MainNet will pause and go offline at the start of the major upgrade, 9 am US Eastern (1400 UTC)
   • MainNet will remain down between 3 and 6 hours
   • This major upgrade with downtime was approved by a vote of the Super Validators to adopt CIP-0089
   • The proven upgrade path is 0.4.23 -> 0.5.1. You must upgrade your Validator to 0.4.23 or 0.4.25 before the major upgrade.

    

   • Validators will stop processing transactions as soon as MainNet begins this pause.
   • To rejoin the network and resume processing transactions, Validators must complete the migration steps outlined in the technical documentation for Major Upgrades, here:
     • https://docs.sync.global/validator_operator/validator_major_upgrades.html
   • MainNet’s Migration ID will change as part of this upgrade. The Super Validators will announce the new Migration ID once MainNet comes back online. The default Migration_ID value will be 4, unless announced otherwise by the Super Validators.
   • Every node should take a full backup of its node and identities before the upgrade. Details here:
     • https://docs.sync.global/validator_operator/validator_backups.html#backups

   Important Points:

   • Before initiating the upgrade procedure, Validators should confirm that their nodes do not have any Ledger API users without party-level permissions
     • See the example provided here:
       • https://github.com/global-synchronizer-foundation/docs/discussions/19#discussioncomment-15013845
   • Exchanges and other Application Providers should read closely through the additional guidance provided here:
     • https://docs.digitalasset.com/integrate/devnet/exchange-integration/node-operations.html#rolling-out-major-splice-upgrades
   • The proven upgrade path for this upgrade is Splice 0.4.23 -> Splice 0.5.1.  All Validators must upgrade to Splice 0.4.23 before the upgrade.
     • Upgrading to Splice 0.4.25 is optional; the 0.4.25 -> 0.5.1 upgrade path will also succeed.

   Note that, as outlined in the long-term schedule, this major upgrade will be followed immediately by a minor (non-forking) upgrade to Splice 0.5.4.