Boo to you, Claire, and welcome to the spookiest corner of the Internet...
planDisney! Thank you so much for stopping by with your ghoulish question!
I'm very happy to report that
Mickey's Not-So-Scary Halloween Party will most definitely be held on September 5, as well as September 7. I checked both the Walt Disney World Resort website and the My Disney Experience mobile app, and both dates show up on both sites. You might've just come across a glitch!
Claire, if you're going to be staying in a
Disney Resorts Collection hotel during your vacation, you can actually go ahead and purchase your Mickey's Not-So-Scary Halloween Party tickets now. However, if you're going to be staying elsewhere, you'll be able to purchase them on May 22. I strongly advise that you get your tickets as soon as you can, because this event does tend to sell out pretty quickly every year. I mean, of course! It's the BEST event of the year in my honest opinion!
Remember that adults are more than welcome to wear costumes to the party in addition to the kids, so don't be afraid to go all out with your costume! Just keep in mind that long capes, masks, weapons of any kind (including toy guns), and dresses that drag on the floor are not allowed... but everything else is fair game! Feel free to dress up like your favorite Disney characters and enjoy like a little kid for one night. I know I will!
I hope this helps, Claire. If you have any other questions, please don't hesitate to
reach back out to me so I can assist you further! Have a spooky day!
Warm hugs,
Ana Paula