George R.R. Martin provided an update recently on the progress of his work on "The Winds of Winter" - that release date of the book, the sixth instalment in the "A Song of Ice and Fire", will happen this 2017. But that is far from confirmed. What's likely set in stone is that Season 7 of "Game of Throne" will run its full course and TWoW will not see publication.
HBO and GoT showrunners David Benioff and Dan Weiss have made clear that it will be a summertime airing start for Game of Thrones this 2017, indicating that again the fantasy-drama series will outrun Martin's upcoming book. According to Insider, Benioff and Weiss can wrap up show without waiting for GRRM to finish TWoW.
That's because "the showrunners may already have all the information they need to complete the series in their own way," the same report added. Insider also claimed that the last time Martin met with the Benioff and Weiss to discuss Game of Thrones was after Season 4, purportedly to focus his energy on TWoW.
This was revealed by authors Elio García and Linda Antonsson to Insider, which added that the two collaborated with Martin in completing the ASOIAF companion book "A World of Ice and Fire". With the piece of information, the duo also stated that GRRM is now working on The Winds of Winter unmindful of the release schedules for Game of Thrones Seasons 7 and 8. So essentially, the expectation - that the book will come out first then the show will air - does not apply anymore.
And given that the GoT creator has refused to set a deadline on when TWoW manuscript will be delivered, the chance is high that the sixth ASOIAF launch will not happen until HBO is done broadcasting the seven episodes produced for the Game of Thrones this 2017. The cable channel said GoT Season 7 will premiere around mid-summer this year and the whole run will only last seven weeks, somehow indicating that Benioff and Weiss will again overtake the notoriously slow Martin as far as The Winds of Winter is concerned.
Hence, there will likely be an abundance of TWoW spoilers that will find their way on the last two seasons of the Game of Thrones, which will end 2018, but the two will not necessarily share the same ending. As mentioned above, Martin has given the green light for Benioff and Weiss to finish GoT as they see fit. But GRRM's work on The Winds of Winter is all his. And per the Insider report: "The only person who knows and understands the full scope of what's happening (on The Winds of Winter) is Martin."