I was one among those who tracked the FP data from this summer, but DL has so many different factors contributing to unexpected changes so I wouldn’t rely much on the data that isn’t immediately near to the dates you are going as trends may be different. For example when I was tracking FP times this summer, Soarin/Star Tours/Guardians of the Galaxy had very big fluctuations in their FP distributions. Some days they seemed to last for very far into the day, hardly moving the needle & then other days they were among the first to go. All of them have multiple theaters/loading areas and if a portion of those are down for the day the FP capacity will be impacted causing FPs to run out much quicker than anything else, just because of the diminished capacity.
Also, when Space Mountain or Haunted Mansion have an overlay or to a lesser extent, are recently returned to their original forms following an overlay they tend to run out much faster. In a similar vein, anything that’s new (like Incredicoaster was this summer) is faster to run out & it’s a combination of the overall capacity and the public’s reception to it that causes it to steadily be the fastest to run out, or if it dips again after the initial newness wears off (RSR while it is not nearly as bad as it was its first years, has very rarely since it’s opening been de-throned as the 1st FP to run out between both parks).
All of this combined with less user input to the Lines App makes the fastpass return times predicted in a plan to be MUCH different than what actually occurs. I do still like making a plan to have a checklist in front of me, but if it’s a plan that we really are wanting to stick to (and if I have the time) I will stalk the Disneyland app for the FastPass return times to see how my plan would work out & add notes of what Plan B or C may be if we need to adjust to fluctuating FP times.
When checking the app for the FP return times it’s important to note that you want to pick a day with the same operating schedule as the day you will be touring - so you’ll want the same opening/closing time for both parks & a day that the park with early entry is the same as the day you will be touring.
If your day’s hours haven’t been officially announced, use TouringPlans’s predictions of the hours for the day, but really, echoing what I mentioned above, I wouldn’t rely on data from that far out. Disneyland will release the park hours 6 weeks in advance & that is probably on the outer edge of dates that I would rely on for tracking my plan. And also try (as much as can be done since Disneyland’s scheduling can be announced as late as 2 weeks before the planned event date), to account for any non-ticketed special events/offereings that are known (i.e. Food & Wine or Holiday Festivals, Lunar New Year Festivities, AP Days events, new seasonal decorations accompanied by changes in entertainment) as the first day of these events will draw a lot of bloggers/media to the event to share with their masses of followers & report back.