Aye, sorry bout earlier comments, hard day at work and all that (as in I actually did some…).
There’s nothing in the setup of the site that would make the PCs be logged in automatically. 2 things I would do:
1) See if the internet cache is shared for all the machines in the room. You could be feeding from the college cache rather than a local or from the actual site.
2) When it happens hit CTRL-F5. If it brings you back to the login style page, then you know its a cached page.