We identified an issue in our recent release of Operate 1.1.0 (part of Camunda Cloud 1.1.0). This issue only applies if you are updating from a previous version of Operate 1.0.x to Operate 1.1. We recommend to NOT update from 1.0 to 1.1 right now. We are working on a solution and will update you once a fix is available. The issue can be tracked here: https://jira.camunda.com/browse/OPE-1343
Zeebe (Workflow Engine) is not affected by this issue.