It depends on the role, actually! I can give you the experience from one of the most common types: the back-to-back tagout.
So we’re all familiar with boo holes, which are the hidden spot, typically behind a curtain, that a scareactor emerges from when performing their scare. These boo holes are typically connected to a backstage “hallway” or larger space beyond the visible, decorated walls of the house where team members can exit from guest view. If the hallway is large enough, an event called a tagout takes place.
Here, tagout is used as a reference to the action as well as one’s other-cast partner. Cast A performs for their set for 45 minutes while Cast B takes their break for that time. When the 45 minutes are up, which is a strictly-enforced schedule, Cast B goes to their respective boo holes. The most common method of letting the member of Cast A know that their Cast B tagout is there to take over is a tap or a “tag,” hence the name. This way, the member of Cast A can hit their trigger, perform one last scare, and quickly step back behind the curtain of the boo hole to allow Cast B to fill in their place. This allows for a seamless transition with minimal pauses between scares.
Another type of cast change, which I am less familiar with, would be the type where they completely stop guest flow to allow the change to happen. Killer Klowns does close at the 45 to allow for the cast change, presumably because of the movement limitations of the Klowns making it difficult to fit two people by each other.
Ghostbusters will close only because Janine, the only live speaking role in the house, must switch over her mic to her corresponding Janine.
The complete house pause can also be due to character integrity issues; I know that last year, Halloween 4 apparently had to take a moment between sets because of the risk of seeing more than one Michael Myers at once in the same place. Lastly, some roles call for harnesses and other difficult pieces of rigging that cannot be simply stepped away from and into, such as the flying witch from last year’s Scary Tales.
Street cast changes are simple. They tend to end with a show scene of some kind;
the Chainsaw Drill Team makes a large huddle only to burst out at guests, chainsaws all running at once, and a Zombieland set will end with a Zombie Kill of the Week show.
Vamp ‘85 would end with one of the ball drop show scenes. Instead of the crowd of actors running around the zone without a predetermined target, the cast change calls for them to run backstage. Look for an ops member holding and spinning a small blue glow stick in a circle to signal this event.
I’ve heard from a friend of one of the Little Rocks that she specifically waited for Wichita’s show scene to end her set, and was surprised when she didn’t show up on time.
I hope this helps! I’m not a scareactor, but I have many friends and a boyfriend that are!
Edit: yeah, what Legacy said ! I’m a bit over-explanatory!