JSU provides a concept of preconditions which are on the JSU Server/DC App implemented as Post-Functions. Following Post-Functions can use the result of the Preconditions to either be executed or not.
Due to the nature of how Post-Functions work (async mode) on Jira Cloud we directly integrated the precondition into the actual Post-Function. Precondition Post-Functions are not standalone on the JSU Cloud App.
The migrated Precondition Post-Functions do not exists in the JSU Cloud App, but we required the configuration of them to merge them into the actual Post-Function on the cloud side. After finalizing the migration, the Precondition Post-Functions are no longer required and can be removed.
The removal functionality of workflow transition rule does not exists and so we are not able to provide our common customers a seamless migration.
provide a delete workflow transition rule endpoint (https://developer.atlassian.com/cloud/jira/platform/rest/v3/api-group-workflow-transition-rules/) for app owned workflow transition rules for migration purposes.
this would provide us the ability to perform a proper migration of JSU precondition Post-Functions and do the required cleanups afterwards.