Info on when AOE3 DE will be revealed

From Devs:

"I’m happy to tell you that we’re going to start talking about Age of Empires IV later this year. As you know, there are two major events right now – Gamescom and XO – that Microsoft always does stuff for. So one or the other, maybe? I can’t be specific, but suffice to say that we’ve got Gamescom coming up, and then XO later this year in London, so at the latest, you’ll hear more about Age of Empires IV by XO. I will say that later this year, we will start taking the wraps off both Age III and Age IV. "

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https://www.pcgamesn.com/age-of-empires-2-definitive-edition/new-civs