Hi Hanna!
Thanks for your question and for visiting the Disney parks Moms Panel!!
I like how you think....
Mickey's Very Merry Christmas Party is one of my and my girls' MUST DO's on fall trips to
Walt Disney World! Seeing it snow on Main Street U.S.A. gets us EVERY time. PLUS the unique character greeting opportunities, the special fireworks show, Holiday Wishes, and Mickey's Once Upon A Christmastime Parade are all spectacular and worth the time and money to attend!
As for the actual 2019 dates for Mickey's Very Merry Christmas Party, I would stay tuned to the
Disney Parks Blog for the latest breaking news on release dates. Also, I would expect them at any time as Mickey's Not So Scary Halloween Party event nights have been published for a bit of time now, and the Christmas dates usually follow soon after.
I hope this helps and I wish you a Magical trip this fall!!
Chris