Oh my god!! The exact same thing happened to me two days ago (you can check my post history and see how panicked I was lmao) since I had no idea the school email was going to deactivate.
I emailed my school IT department but only because I also signed up for iCloud with that email and it’s completely useless now that it’s deactivated.
Episode-wise, I submitted a ticket asking them to change the email associated with my episode account, but it’s been two days and they still haven’t answered since they are really slow with these types of things
I hope your problem gets solved too… I really cannot believe that episode doesn’t have a email change form that users can use, it makes me question how functional the site is as a whole honestly.