The Witcher 3: Wild Hunt's two future story expansions combined will be "almost the size" of the entirety of The Witcher 2, developer CD Projekt RED has said.
In an interview with Game Reactor, Konrad Tomaszhiewvicz noted that both expansions will introduce completely new storylines, including additional cutscenes, quests, items, and other content.
“The first expansion will be around 10 hours and the second expansion will be around 20 hours… and I think it’s possible that they will be bigger,” he commented.
“It’s always like this (that when we plan some time or hours, it’s twice or something like this), but I’m not promising anything right now. And even now, if you sum up this 10 to 20 hours and you compare it to The Witcher 2, it’s almost the size of The Witcher 2. And it will be cool, it will be new stories, it will be very emotional stories and I think that people will be happy.”
Hearts of Stone, the first expansion, is scheduled to release in October, while the second, Blood and Wine, will arrive in early 2016. Both expansions are included in the game's season pass and you can find out more about them here.