On the Copy patrol interface, after a user has chosen a triage state, that user can undo their own review.
On an item that the user has reviewed, when the user clicks on either button, a confirmation message pops up: Are you sure that you want to change the review setting? Yes / No. When the user confirms, the state goes back to untriaged.
Untriaged state:
Reviewed:
Changing review, with confirmation: