Expired FP can cause issues for booking tier 1 FPP as a forth FP. One of the touring plan staff did a test on this. If you are in a park with tiers and you let one of your three FP expire, then you are not able to book any additional FP that park in the tier 1 category. It was in a discussion about booking only 1 FP (tier 1) in a park and then being able to book another tier 1 FP same day in a different park as your second. I will see if I can find it again. Changes to FP+ - #19 by SteveBloom