[2] Her doctorate was awarded for her thesis "The Pre-Conquest History and Archive of St Augustine's Abbey, Canterbury".
[3] From 1985 to 1988, Kelly was a Rank Foundation Research Fellow at St Catherine's College, Oxford.
She was then a British Academy Research Fellow at St Catherine's from 1988 to 1991.
[4] She has been a Marc Fitch Senior Research Fellow at the University of East Anglia since 2015.
[1][4] In 2016, she received the President's Medal from the British Academy, the United Kingdom's national academy for the humanities and social sciences; awarded to up to three people annually, the medal recognises "outstanding service to the cause of the humanities and social sciences".