"The Winds of Winter" release date is taking over six years and some fans are already becoming impatient waiting for the next instalment for the "A Song of Ice and Fire" series. George R.R. Martin teases "dark chapters" in his sixth book, as two of his most trusted friends explain the reason behind the delay in the release date.

The latest "Winds of Winter" updates reveal that George R.R. Martin likes to take his time in writing his books. While readers of the "A Song of Ice and Fire" series are already aware of this fact, his friends Elio Garcia and Linda Antonsson gave Insider possible explanations as to why the 68-year-old author is taking a long time.

Antonsson told the publication that one of the reasons behind the delay in "The Winds of Winter" release date is Martin's refusal to create an outline for the story because he may end up getting bored. In a previous interview, Martin likened his style of writing as the gardener type who likes to take his time and see what happens along.

The HBO series, "Game of Thrones," may have also taken some of GRRM's time to finish "The Winds of Winter," as the author grew in popularity because of the show. Martin has also written one episode of "GOT" till season 4.

Meanwhile, "The Winds of Winter" is expected to be released this 2017, as per Martin's latest update in his blog, reports Independent. According to the "ASOIAF" author, he has "made progress" with his sixth book, but not as much as he expected in the previous year.

Martin teased, however, that readers should brace themselves for "dark chapters" in "The Winds of Winter." According to Martin, he has been telling everyone about the ominous things that take place by the time winter comes.