Thank you so much for taking the time to give such extensive feedback.
I am definitely going to have to mull over the idea of it being the first day of school. I might write a version and see how it reads. I agree that would make the anxiety much more intense (and relatable) but I worry it might make the situation less desperate i.e. if you have been there a couple of months and you still don’t have friends then you would feel very anxious. But maybe it doesn’t matter.
I really like the idea of the prefects showing her around as that might open up a different set of tensions and actually could maybe even be an entirely alternate first chapter. And I like the idea of her seeing a glimpse of her future self. I think you are right that the full realisation that it is her a double of her should come along later. But it could be foreshadowed. I am going to have to see if I can cut a few of the items (like the inspectors) and see if I can expand on some of the core things.
Thank you very much for investing more time in my novel! Very much appreciated! :D