If there will be a major expansion for the summer, which I have no doubt on, I don’t believe at all it will be “30th Anniversary” by name or theme, let alone be a mix of both novel, film, and original content in any way, shape or form. Because, based on how Frontier has built their past PDLCs and updates that add new free things for Jurassic World Evolution 2, and even a little bit on the first game’s content, there’s no reason for me to believe any of those scenarios will be the case.
Because of this, there are three theories, which I think are more realistically plausible, of what I think a possible next expansion will be for the summer. The first is a “Camp Cretaceous Expansion” where it introduces not only any of the species the CC Dino Pack doesn’t have, but also a campaign set on both Isla Nublar and the secret island where you play with operations set on both islands, and cutscene cinematics from the show with Darius being the narrator.
The second is a “Dino Tracker / DPW (or something like that) Expansion” where it adds a campaign set after Dominion with cinematic scenes from that movie in its cutscene(s), maybe Wu or Grant as the narrator, where you help the DPW, with DPW themed building sets, with the dinosaurs all across the globe instead of just the USA as with the DFW campaign. Since I don’t believe they will ever mix a film appearing animal with their own original created ones, and they’ve never done that before, I think all of its dinos will be original with no Microceratus.
The final theory is a “Site B Expansion” where you explore an original narrative campaign set from its beginnings, all the way to its downfall. It might have cinematics from across any of the six movies (undoubtedly The Lost World and Jurassic Park III of course) and maybe Wu as the narrator, a Site B building set, and maybe the Microceratus along with skins and/or variants from the original trilogy, if any.
If there will be something “30.th Anniversary” related for the game, my only guess is the major free update when a possible summer expansion will release, adding a thing or two from all six films.