You may even be able to unlock it sooner actually. When the game prompts you to drive to Nice you drive past the Storm Island marker and it plays you the video - I’m unsure if you can access SI directly at this point or if you must still finish the first set of 3 road trips. You must “take the boat over” and do the Storm Island intro race the first time you wish to go there and race in Free Roam.
Storm Island is only accessible when you 1) reach Sisteron to complete the third championship in the game’s initial road trip and 2) when you return to the Forza Horizon festival hub to complete the “awards ceremony.” This not only unlocks Storm Island, but various in-game features that would have been inaccessible up to this point. Simply: you cannot proceed to Storm Island until you have completed these two prerequisites.
When my wife began playing Horizon the game played the Stom Island intro video upon driving by the marina in Nice the very first time. This occurred en-route from the Castelletto road trip to the Nice road trip. Just because the video played does not mean that travel was available.
As I wasn’t playing myself I’m not sure about whether or not it would allow you to travel. The Shadow Edge are you saying that even though you get this introduction, you cannot access Storm Island until after completing the initial road trip? This is what I thought but second guessed it since ^…