Automation to clear/delete subitems

We have different subitem task lists associated with different phases of work, designated via groups or statuses within a board. We have an automation set up to add subitems when the item is moved or updated, but these subitems tend to accumulate, whereas we don’t need to retain the completed subitems from the previous phase of work.
My request is that an automation capability be added to clear subitems, similar to existing options to clear a column or assignees.