On the Practice Management tab on the settings menu, there are two available admin tasks:
Delete all jobs and tasks
This will remove all transactions related to Practice Management, you are then able to disable the Practice Management module.
Close completed jobs
The system will check for those jobs where the status on the return or accounts has been accepted by HMRC or Companies House, but the tasks have not all been marked as completed. The system will mark these jobs as closed. Where there is not a job for the next year a new job will be created.