According to the Disneyland Resort website and app, Space Mountain will be closed on April 28, 2022, and reopen as Hyperspace Mountain on April 29 for a limited time.
Here is the description of Hyperspace Mountain from the Disneyland website: “Hurtle through hyperspace while dodging furious dogfights during this high-speed Star Wars adventure—opens April 29!”
The overlay seems to be for the upcoming Disneyland After Dark: Star Wars Nite events and May the 4th (Star Wars Day).
Star Wars: Hyperspace Mountain currently exists as the apparently permanent Space Mountain overlay in Disneyland Paris and Hong Kong Disneyland.
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