There was a change to use Deployment instead of DeploymentConfig for syndesis-operator in 1.12 branch . That causes that upgrade scenario doesn't work because when `install operator` command is run on 1.12 operator, it creates Deployment but doesn't delete the old syndesis-operator DeploymentConfig from 1.11 version. Due to that, the upgrade stuck because the older syndesis-operator still exists and the new operator is only waiting.
I see two possible solutions.
1. Before run `install operator` command in upgrade script, the syndesis-operator DC should be deleted `oc delete dc syndesis-operator`. But this cover upgrade only install/upgrade script.
2. `install operator` command delete also dc syndesis-operator. In my POV, this solution is better because doesn't cover only the upgrade script.