I know the standard recommendation (without a FP) is to get in line 60 or 90 minutes before the show starts to get one of the best seats. If I am comfortable with just any decent seat, what can I expect if I get in line only 15 minutes before the show starts? Is there a chance at that point that it will be "sold out" and there will be no seats left at all, or does that just mean I will get a less-than-ideal seat?