Hi Bradford! Thanks for bringing your question to planDisney.
Meeting our favorite Characters is often the best part of a Disneyland Resort trip. It really is a special kind of Disney magic. On our most recent family trip, we even added a new Character to our growing list of interactions. Raya is my youngest son's favorite Princess, but we'd never gotten the chance to meet her, so our Character Experience at the
Disney Princess Breakfast Adventures in Napa Rose at Disney's Grand Californian Hotel & Spa was extra special. Incredibly tasty too!
I understand your eagerness to plan your visit around these interactions. Unfortunately, there is no way to guarantee this far out that any of the Characters you'd love to snap a picture with will either be roaming or at a Meet & Greet location. I can't give you a hard and fast answer, but I can suggest how you can determine if they might be around as your visit draws closer.
First, download the
Disneyland mobile app, then locate the map feature. Change the selection on the map from "Attractions" to "Characters." This will bring up Mickey Mouse icons throughout the parks, and if you tap an icon, you'll see which Character you can expect in this area. It will also let you know when you can hope to encounter them. These Characters and schedules are subject to change, but hopefully, it's a handy tool to help plan your day when you arrive.
For example, by checking the app, I can see Guests could meet Chewbacca today in Star Wars: Galaxy's Edge by the Millennium Falcon in Disneyland Park. Whether you can meet him in September, however, is uncertain at this time. I can tell you I've been lucky enough to run into my favorite Wookie while enjoying a beverage in various locations on Batuu. He stopped for a quick photo with me and my boys. Maybe you will be lucky enough to run into him too. Never tell me the odds!
May the Force be with you.
Elizabeth