Sarah J. Maas just did that
I got to the first page of chapter 78 and started loosing my mind. You cannot just do that to me at the end of the book. At first I was thinking I was off base. There was no way she would pull that and it could just be some random nice city with a river and some good grass not OUR nice city you know. But I always remembered SJM saying (loosely) “sure they are connected like dimensionally but unless we’re hopping universes it’s not like anythings going to happen.” So Yah. I was yelling at my book and pacing and generally (see above) loosing my mind. Of course, everyone had to show up and our favorite scary friend could translate and I guess we have an interdimensional group project on our hands. Then the final sentence actually left me dead on the floor. Now you are going to tell me “the book just came out it’s going to be ages until the next book comes out” and I am going to have to say “yes of course” (while theorizing silently and screaming into the void).