I sort of think the gold trophy things isn't a permanent change. It's just more a "focus on this Toy Story 4 stuff." If you look who drops stuff, it's Toy Story Characters, plus Mickey & Goofy (starters, who seem to do everything.) and Pluto (probably the first premium anyone got). There are 4 attractions, two of which are Toy Story ones. Goofy's House (which could be a 'starter content' thing). The Jumpin Jellyfish and Enchanted Tiki Room are odd choices, but maybe the Jellyfish is included because DCA is turned into a Pixar park and it's similar type of ride as the Green Army Parachute. I have no idea why they picked Tiki Room.
Without knowing how Update 31 will affect anything, I would assume whenever we have a normal Trophy mini event, everyone we are used to collecting the would be available. Or this is the start of shorter, more themed events, where who can collect is dependent on the theme of the prize.
But yes, it would be nice if they told us, heck, anything! All this back to back mini, mini-events is not helping with player burnout. Update 31 better be good, or I think everyone will just throw up their hands and delete the game. It's like everyone at GL looked at "Lucy, Charlie Brown and the football," and said, "Look at Lucy, she clearly knows how to win hearts and minds! Let's do that."