Login on a website with an account whose category has been restricted temporarly from logging in

So I think the title is quite unclear so I explain.

Basically, there is a website used by schools in France on which we can see homeworks, grades, send messages,etc. However, a few days ago, the access was restricted to the students and it will be so until 1st september. When I login with a pupil's account, it says that I can't as I am a student and it adds "?connection-state=locked-from-etab-el" to the URL. When I modifiy this line, and retry logging in, instead of the warning restrictive message, it shows what I've written (for instance, if I write ?connection-state=this-is-a-test, it shows connection.state.this-is-a-test) so I wonder if there is a way to login modifying the URL or else.

Thanks in advance