If you look at the online eating out guide in the sticky above I think that that site has a link to the Wendie site that explains everything. Its basically eating more points one day and less points the next to keep your metabolism up. Let us know how you get on if you try it.
Ive never tried the Wendy Plan though I know a lot of people swear by it. From what I understand of it you shouldnt do every week, its more for if you hit a plateau to try restart your metabolism.