In PSOhub, it is possible to delete a task board as long as no time entries have been booked towards the tasks.
Choose from the menu Tasks and Boards.
Here, you will find all your task boards. Click on the one you wish to delete in order to open it. Once in your task board, click the More button and then Delete.
PSOhub will now ask that you confirm this action that cannot be overturned.
Once you click Proceed, the task board will be deleted as well as the task lists and tasks associated with it.