Basically, if it's currently only about fifteen pages (and if it's only fifteen when you apply to get on the list), you should have read only fifteen pages. In other words, it's not really about how much you're going to have so much as it is how much you have when I go to check for fair trading (which is right after you apply).
Of course, given that there's only two fics on the list at the moment, I'm going to be a bit relaxed either way, so don't worry too much about it.