This is copied directly from the Disney website regarding Rider Switch. It indicates it can be used for guests who are unable to ride, not just kids who don't meet the height requirement:
Rider Switch
This handy feature allows adult Guests to take turns waiting with youngsters or Guests unable to ride.
What Is Rider Switch and How Does It Work?
If Guests in your party can’t or don’t want to board an attraction, you don’t have to miss out!
If a child does not meet the height requirement or a Guest does not wish to board a particular attraction, no problem! With Rider Switch, one adult can wait with the non-rider (or riders) while the rest of the party enjoys the attraction. When the other adult returns, they can supervise the non-riding Guests, and the waiting adult can board the attraction without having to wait in the regular line again!
Rider Switch is available at select attractions at all 4 Walt Disney World Resort theme parks.
To Use Rider Switch:
1. First check with a Cast member to see if Rider Switch is offered at the attraction in question.
2. Once at the attraction, approach the greeting Cast Member with your entire party. At least one adult member of your party and the Guests who are not riding will be given a Ride Switch pass and asked to wait in a designated area (usually outside of the attraction). This group is “Party 2.”
3. The other party members (“Party 1”) ride the attraction.
4. After riding the attraction, Party 1 locates Party 2 and gives the Rider Switch pass to the adult member who will be riding. Party 1 takes over supervision of the non-riding children or Guests.
5. Party 2 enters and boards the attraction without having to wait in the regular queue a second time. The Rider Switch Pass must be presented to a Cast Member at this time.
If the person in Party 2 waited alone with the child, he or she may bring one other Guest back to ride the attraction with him or her. Please note that only 2 Guests are allowed per Rider Switch Pass.
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Attractions Offering Rider Switch
Get a complete list of attractions at Walt Disney World Resort where you can use Rider Switch.
Magic Kingdom Park
The Barnstormer
Big Thunder Mountain Railroad
Seven Dwarfs Mine Train
Space Mountain
Splash Mountain
Stitch’s Great Escape
Tomorrowland Indy Speedway
Epcot
Frozen Ever After
Mission: SPACE
Soarin'
Test Track
Disney’s Hollywood Studios
Rock ’n’ Roller Coaster Starring Aerosmith
Star Tours® - The Adventures Continue
Twilight Zone Tower of Terror
Disney’s Animal Kingdom Park
Avatar Flight of Passage
DINOSAUR
Expedition Everest - Legend of the Forbidden Mountain®
Kali River Rapids
Primeval Whirl
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Family Planning Tips
Pick up some tips for an upcoming trip, including fun attractions and experiences for Guests of every age!
Check out the following planning guides for the many members of your family—from toddlers to grandparents:
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