What is the ruling if a husband, during a period associated with religious innovation (*bid'ah*), claims he misspoke by saying 'according to the Sunnah' and intended immediate pronouncement?

Primary text

If the husband states that saying 'according to the Sunnah' was a slip of the tongue (*sabaqa lisani*) during a time of innovation, and he actually intended the pronouncement to take effect immediately, his claim is accepted. This is because he possesses the authority to enact the divorce, and when he confesses to an action that validates the divorce (immediate effect), his confession is accepted.