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Answer: You could replace the staged construction load case by a chained sequence of staged construction load cases, each of which would be using stiffness at the end of the previous load case. The results for a single stage could be then obtained by setting up a load combination that would include the current load case with a scale factor of 1 and the previous load case with a factor of -1. See Obtaining results for individual stages of a staged construction load case test problem for an example model illustrating this concept.