Forge CLI provides version bulk-upgrade command, where we can get the list of issued upgrade command like this.

forge version bulk-upgrade list -e production

The output of this command lists *Failed* counts, but there's no way to find out which site upgrades had failed and why.

Please add more details in the failures. Ideally, this should be visible through developer app console where we would be able to look up *Upgrade ID* and see all the failure details.