Thanks Steve!

I also got this response directly from the PASS organisation team:

While registering, it will ask you what you would like to register for on the agenda page – first it will list the pre/post seminars and then the full summit. You are going to click “Discounted Registration” and put the code in the box right below. Let me know if you have any problems and I can help you out.

Just in case anyone else was wondering 🙂