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If an FDateTime variable is created in code and has a default value set in blueprints, any instance that is set to the blueprint default value changes to the code default on hot reload. This includes setting instances to struct default if no explicit default is set in code.
If the instance of the variable has been explicitly set, the hot reload does not affect the instance.
No - same behavior occurs in 4.14.3 (CL 3249277)
StartGameDate value of the instance changes after hot reload
Blueprint default value overrides code based value after hot reload
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