I would say maybe 4:15/4:30pm, gives you an hour or so to eat then gives you time to head to Fantasmic and wait in line. You will probably have to be in line at least 1 hour before show time.
I have to point out that guests can indeed arrive an hour before show-time,
but they will not be "standing in line for an hour."
The theater seating will be opened to guests about an hour or more before show-time, and guests will be walking (in a line, yes) for the distance between the entrance gates and the seating...
But, the line will empty into the seating within 5-10 minutes, give or take, and the guest
will actually be seated in the theater for the vast majority of the hour wait.
That is a very important distinction.
Grabbing a FP+ for F! can also be a good idea.
What a FP+ for F! offers is more CHOICE in seating.
If you DO get a F! FP+, you can choose to sit in either the FP section (virtually the entire left half of the theater) or the Standby section (virtually the entire right half of the theater.)
So, whatever section has the better seating at the time you arrive, you can go there.
Without a FP, you can only choose a seat in the Standby section.
There is a very good chance that you can get a FP+ for F! as a 4th or 5th FP of the day because they issue SO MANY of them (enough to cover nearly the entire left half of the seating.) On many nights, it is possible that you can gat a FP+ for F! as you are walking to the theater.
As to when to arrive at the theater, I'd get to there 45-60 minutes before the show-time.
Even with a FP or Dining Pkg. reservation, don't wait too late.
On
busy nights, the CMs can stop holding the reserved sections within 20-30 minutes before show-time, and turn over any available seats to waiting walk-in guests.
There is sometimes a "pre-show" (such as it is) that can help pass the last 30 minutes before show time.
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Map Below-
Arrows indicate the center of the seating.
Shaded areas:
(First or Only F! performance of the evening)
Cyan= Standby (walk-in) seating
Red= Dining Package Reserved
Blue= FP+ Reserved
Purple= Can be either FP+ or Dining Plan Reserved, depending on needs.
(Second or Third F! performance of the evening)
Cyan= Standby (walk-in) seating
Red, Purple, Blue= FP+ Reserved
(Although much of the outer Blue will likely be used for Standby.)
