I think something we need to keep in mind is how special these upcoming anniversaries will be. We just lost Richard Sherman who made an appearance on July 17, 2015, to play Feed the Birds in front of the castle for everyone. Others there that day include many members of the 1955 Mickey Mouse Club who have passed since. Ron Miller (Walt Disney's son in law) has passed, too. Many of the original 1955 Cast Members and Imagineers who were there that day in 2015 are no longer with us, as well.
70 years since 1955 is a tremendous amount of time to spend on this earth, especially for anyone who worked around or was close to Walt Disney and spend a portion of their lifetime working for the company. Whoever significant makes it to Disneyland that day or takes in part celebrating 70 years of Disneyland any time during the anniversary celebration, make sure to take in every moment, as it could be one of the last times we see them enjoying yet another day at Disneyland.