You could ask the department, usually that's what you do if you want to get a seat in a course. You might have to harass them a bit, depending on how busy they get.
You should probably try Alastair Tracey first, since I lost the list of who to contact for course permissions, though I'm not sure if he can add you.
Anyway, this e-mail for the courses are
[email protected] and
[email protected]. Keep in mind that summer courses are running now, so it might take a while to get a reply.
But by far the easiest thing to do is lurk on SOLAR to keep watching it, and then take whatever you can get for times and tutorials, you can always switch lectures or tutorials if you have a time conflict, just email Alastair.