Just kind of thinking, is it really "changing" what happens in the books if you're just showing what happens in the books in chronological order? The issue with Song of Ice and Fire is that it's not in order, Martin wrote a lot where he'd move the plot forward by months, then backtrack months to cover what happened to other characters. So... yeah, you're not jumping forward in the story just because you move to later books, there's a difference between book order and chronological order. A show needs to maintain a timeline that's consistent as to not royally confuse the audience.
It's interesting that you would choose to comment that the trailer is jumping back and forth in time when that's how the book's narrative actually handles things... yet you've gone and claimed that they're changing what happens in the books by not doing so.