Epic is on it's way and does not appear to be an expansion on Adeptus Titanicus, and not set in 40k. Let's see what is being said.

As said below it is set in the Horus Heresy. 

via source on Faeit 212

• "Epic is coming. The game entered the playtesting phase."
• "Game is set in the Horus Heresy."

Going to be huge when it drops!

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