Hi Jonathan,
Sounds like you have a nice long trip planned! I checked the on-line calendar for your dates of travel. The calendar only show 2 performance dates for Fantasmic! during your trip: Thursday, April 15th at 8:30 p.m. and Tuesday, April 20th at 8:30 p.m.
The schedule is always subject to change, so keep an eye on the calendar. You can do that on-line by clicking
here. Above the top right of the monthly calendar, you will see a
View Month box. Click on the drop down box and select April. That will bring up the monthly calendar showing hours of operation and Extra Magic Hours. To see the daily schedule which will include Fantasmic! (if scheduled), click on a specific day.
For confirmation of the scheduled performance time, be sure to pick up a Times Guide in addition to your Park Guide when you enter DHS. Also keep in mind that Fantasmic! could be cancelled due to inclement weather.
As you can see Fantasmic! is now performed only on select evenings so its very popular on the days that it is held. Be sure to arrive at the theater at least 90 minutes prior to the show.
DHS offers a Fantasmic! Dinner Package which includes dinner at either Hollywood & Vine, The Hollywood Brown Derby or Mama Melrose's and seating in a reserved section of the theater. To check availability call 407-WDW-DINE.
I'll keep my fingers crossed that you are able to see Fantasmic! this trip!