When a substitute request is claimed, a new one-time substitute commitment is created for the adorer who claimed it, and the requesting adorer is notified that a substitute was found.
Thus, a claimed substitute request cannot be canceled.
If the adorer who claimed the substitute request did so in error or now needs a substitute of their own, they can request a substitute! Or an administrator or captain can do this on their behalf.
If the original adorer no longer needs a substitute, an administrator or captain can assign the one-time substitution commitment from the claiming adorer back to the original adorer.