Our exams officer shared this with me.
https://www.ocr.org.uk/blog/supporting-students-with-diabetes-in-the-exam-room/
The answer is yes you can – an application has to be made on AAO – which will come back as “No” but you then click on the button which goes directly to the Awarding Body, who will approve it (I guess that this would then have to be done for all awarding bodies unless that single request goes to all).