Hello
When I've had a student who requires more time to take a test, I ask them to humor me and just take the first iRAT with the class to see how they feel (if they take it and they do horribly, give them the points and make arrangements with them - that's never happened to me though). Usually students who need more time (at least in my experience) are those who have trouble focusing and so need more time. So for one student, I had her team sit in the front because she said as long as no one was in front of her, she wouldn't be distracted. The iRATs were not as hard as the students expected (since they're at a table of contents level) and after taking the first iRAT with the class she decided they were easy enough and was not too distracted when sitting in the front row in order to take it with the class.
Hope this helps!
Meghan