Another bit to supplement my theory that the Night's King's story was about the future, and that Joramun is Tormund, and hence that the show didn't do the actual ending but ended before it:
"He was a good man... No. He was a great man. A maester of the Citadel, chained and sworn, and Sworn Brother of the Night's Watch, ever faithful. When he was born they named him for a hero who had died too young, but though he lived a long long time, his own life was no less heroic. No man was wiser, or gentler, or kinder. At the Wall, a dozen lords commander came and went during his years of service, but he was always there to counsel them. He counseled kings as well. He could have been a king himself, but when they offered him the crown he told them they should give it to his younger brother. How many men would do that? He was the blood of the dragon, but now his fire has gone out. He was Aemon Targaryen. And now his watch is ended."
Jon would be the 13th lord commander under Aemon's reign.
Jon's real name in the books will be Brandon. Which Old Nan said was the Night's King's name.
It makes perfect sense that Rhaegar and Lyanna would name him Brandon out of guilt for Brandon's death, and in his honor. Ned would have changed the name because he wants to put as much distance between Jon and his mother as possible, and especially not give him the name of the one who would have been heir.
Also I just realized Tormund is also known as Horn Blower and Ice Breaker, reinforcing the idea that he is Joramun.
So if I am right, D&D ended the show before the real ending. It's either that or Bran changes the timeline in the books and prevents the NK story from taking place.
"This... this isn't the end. Not for you. Not yet."
"How will we know it's the end?"
"You'll know."
When the weirwoods burns.
Bran was supposed to get Lightbringer, the masterless Drogon, and burn the weirwoods, to finally put an end to the cycle. But in doing so, he would end all the source of magic that powers him. Brandon the Breaker.
"One day, Bran, you will be Robb's bannerman, holding a keep of your own for your brother and your king, and justice will fall to you. When that day comes, you must take no pleasure in the task, but neither must you look away. A ruler who hides behind paid executioners soon forgets what death is."
That was when Jon reappeared on the crest of the hill before them. He waved and shouted down at them."
I'm starting if GRRM didn't literally plan to always hide what the last book would be, where ADoS would actually be a fake "last book", and after it's published and everyone wonders WTF is it really over he announces a new actual ending book. The title "A Dream of Spring" always hinted at the idea that when that book is over the world is still engulfed in winter.