Just want to tell you that the start of Oblivion would be 3E433, not 3E453 as in the recently released FAQ. There is a mistake in the A Brief History of the Empire. Check this thread for more information. It makes the Oblivion starts after 6 or so years after Morrowind events.
I still say 26 years, because he said the end of the third era, regardless of the contradiction of two equally credible times to which he came to power, the end of the third era is closer to 453.
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A man once asked the Buddha, "How does one escape the heat of the summer sun?"
And the Buddha replied, "Why not try crawling into the blazing furnace?"