Daw ei rybudd cyn iddo draddodi araith yng nghynhadledd flynyddol Cymdeithas y Bar ar gyfer Cyfraith Gyfansoddiadol a Gweinyddol, union 24 mlynedd ers i Gynulliad Cenedlaethol Cymru – sef Senedd Cymru nawr – ddod i fodolaeth.
It comes ahead of a speech to the Constitutional and Administrative Law Bar Association’s annual conference, delivered 24 years to the day since the National Assembly for Wales – now the Welsh Parliament – came into existence.