SWIFT ISO 15022 - Code REVR Financial acronyms The entire acronym collection of this site is now also available offline with this new app for iPhone and iPad. Meanings Reversal: Notification of a reversal. Reverse: Message sent to reverse a posting on a previously sent confirmation. Usages Message type Field number Tag MT564 (Corporate Action Notification) 51 22F (Indicator) MT566 (Corporate Action Confirmation) 3 23G (Function of the Message)