I’m assuming you mean sworn in as in post oath of office public ceremony stuff, which I don’t think they’d wait that long. Bc the VP immediately assumes the title and duties, so if that’s what you mean then it would be instant. They’d probably just delay it until the president’s family has been formally informed and the VP was briefed on immediate/emergency matters. Or if it happened in the middle of the night, like 6-8 am the next morning. I don’t expect a 2am amber alert style CHANGE OF PLANS

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