Ticket Template Update?

Hi, In Actions, when using the Create Ticket task, top right you can save and use templates. But, I can't find how to update an existing template... I used the template in a couple of different surveys, and want to add an additional Ticket Data field, so I'd like to add it once to the template and hope that all tasks that used this template would update? Currently I can only find how to Save As a new template... !