In preparation for the upgrade, validators halted the Cosmos Hub 2 chain at 11:39 am UTC. Twenty-five minutes into the migration, validators uncovered an issue with the new genesis file that was caused by the migration command.
Validators deemed that the Cosmos Hub 3 would fail to launch with the instructions provided in the upgrade proposal. They then followed the proposal’s recovery plan to relaunch the Cosmos Hub 2 chain, which resumed at 1:54 pm UTC. The Cosmos Hub was down for a total of 2 hours and 15 minutes.
We are in the process of writing a detailed post-mortem to be published by end of week, and will outline the next steps for the Cosmos Hub 3 upgrade.
Twitter version here: https://twitter.com/Ether_Gavin/status/1176620977163292672